When a young girl is contacted by a man claiming to be her father, Det. Rush and her team reopen a 1988 case of a teenaged boy, killed on the same night the girl was born.

Lilly re-opens the case of young girl, an overweight college freshman named Laurie, who died in a fraternity house fire in 2004. The fire was deemed accidental at the time, but a cell phone photo e-mailed from the girl's phone just moments before her death prompts a closer examination.

The 1978 murder of a young man is re-opened after the victim's mother finds a letter suggesting that his death wasn't random.

Det. Rush re-opens the 1945 case of a baseball player, bludgeoned to death with his own bat.

In 1954, 9-year-old Otis Petrowski last saw his mother in a mental institution. Now over 50 years later, after the death of an elderly woman who had been using Otis' mother's identity, Det. Rush sets out to discover what happened to the boy's real mother.

When a mother of five loses her fourth son to gang violence, Lilly sets out the save the youngest, reopening one of her first cases on the homicide squad.

Lilly re-opens the 1999 case of a young, healthy woman who nevertheless died of a heart attack. In the late 1990's, she was briefly an Internet millionaire, but due to bad business decisions, her dot.com company eventually went bust.

When a box filled with POW support bracelets is found in an abandoned drug den, Det. Rush re-investigates the 1972 shooting of Carl, a veteran of the Vietnam War.

When a fisherman finds evidence of a young girl's death washed up on a shore in New Jersey, Lilly re-opens the 1965 case of 4-year-old child who had a seemingly abusive mother.

The team re-opens the 2001 case of a robbed and murdered deli owner when the brother of the man convicted of the crime brings forth new evidence, suggesting the man may have been wrongfully accused.

Four close high school friends each went their separate ways in 1980. Eight years later, in 1988, one of them was murdered. The homicide team receives a tip about the murder, prompting a re-investigation of the case and an examination of the friends' lives, hopes and dreams after high school.

When a note connected to a supposed suicide is found, the team re-opens the 1994 case of a high-school kid who fell from the roof of the school building after having served detention. In 1994 the death was deemed a suicide, but the newly-found note indicates that the victim might have been fearing for his life.

Lilly re-opens the 1968 case of an 18-year-old girl who died -- apparently accidentally -- at the night of her debutante ball. Now her mother comes forth with new evidence when a local art dealer is accused of murdering his wife in the same manner the girl died.

The case of a female bank teller shot to death in her work in 2000 is reopened when the same bank is robbed again by perpetrators wearing identical masks and equipped with identical weapons as six years earlier.

The 1998 case of a female drug smuggler is re-opened. The woman was involved with Scotty at the time he was working undercover on a high-profile drug case, and he has been keeping it a secret from the team for all these years.

Lilly and the cold case team will have to decode the clues given by a twisted killer in order to save the life of a young boy who has been left to die alone. But first they must find the boy and for that they need to dig a little deeper into their own pasts.

When a poison-soaked towel turns up at the station, Lilly re-opens the 1973 case of a murdered female college tennis star.

The team re-opens the 2002 case of a murdered amateur actor when the owner of a local community theater finds a gun hidden inside prop furniture.

Lilly re-opens the 1929 case of a woman found dead in a ravine on Christmas Day when the victim's great-granddaughter comes in asking for help. Meanwhile, Lilly's estranged mother shows up, hoping to re-connect with her daughter.

The 1994 case of a raped and murdered 16-year-old girl is re-opened when Det. Jeffries gets a call from a prisoner on death-row -- scheduled to be executed in just three days.

The 1945 case of a murdered newspaper reporter is reopened when new evidence suggests that the woman was thrown in front of a passing train by someone she knew.

When a new witness steps forward, Lilly and the team are prompted to re-open the 1984 shooting of a respected and beloved ER doctor who had a secret he had been hiding from his family.

When the victim's credit card is suddenly used a year after his death, Lilly re-opens the 2005 case of a counselor at a teens' rehab center who was shot to death just two weeks before he was scheduled to testify in a murder case. During the probe, Lilly feels a strange connection to the victim, and her personal attachment may end up jeopardizing the case.

Lilly investigates a 1995 shooting spree at a mall in which two teen boys killed 15 people before committing suicide. The case is reopened when a video of the crimes is found and it suggests that a third shooter was involved. Elsewhere, Stillman asks Valens to investigate whether Valens' brother may have been molested by a boxing coach in the 1980s.

The team re-opens the 2004 case of a female veteran of the Iraqi War when her prosthetic arm is found in a river. Meanwhile, Scotty visits his older brother in connection with a case that brings up painful memories from their childhood.

When the remains of a sandhog miner who disappeared in 1947 are found in a subway service tunnel, the team is prompted to re-open the case when they suspect the victim might have been murdered for being a union activist.

A 6-month-old girl's 1982 death, originally ruled to be a result of sudden-infant-death syndrome, is investigated when new evidence reveals the baby may have drowned. Also, Lilly learns that Ray is in the hospital after apparently being beaten.

Lilly re-opens a 2003 case in which an autistic boy's parents were shot in their car when Joseph brings her information that the boy might have seen the killer.

The apparent 1958 suicide of a popular rock-and-roll DJ is reinvestigated after a documentary filmmaker discovers a tape recording made at the time of the victim's death by gunshot at his radio station. Also, Valens tries to get his brother to testify against a suspected pedophile.

The 1979 murder of a schoolteacher who was stabbed to death in a wooded area is reopened when the victim's bloodstained jacket is found stuffed in a tree trunk with a happy-face key chain in a pocket. The case was originally investigated by Jeffries when he was a rookie detective.

The 1975 disappearance of an 8-year-old girl who was never found is reinvestigated after a note written by the girl shortly before she vanished turns up. Their friendship rattled many in the predominantly white neighborhood and the girls quickly became targets of hatred.

A homely 33-year-old woman is gunned down in an alley in 1989 and her unsolved murder is reinvestigated when a tape of the victim, made for a dating service, turns up in a suicide victim's apartment. Apparently, it was what the man was watching when he killed himself. Also, Vera moves into an apartment of his own

The team re-investigates the 1968 death of a policeman who was shot in his patrol car. The case was then ruled as a drug bust gone bad, but new evidence now reveals the victim may have been romantically involved with his partner.

Lilly and Valens travel to Nashville and Knoxville to investigate the 2000 murder of a country-music singer who was gunned down outside of a Philadelphia bar where he and his band had recently played. The unsolved case is reopened when the gun used in the homicide turns up.

Lilly investigates the murder of a 17-year-old prep-school student who disappeared in early 2006 and whose body is found stuffed in an oil drum outside an abandoned warehouse in a drug-infested part of the city. Also, Vera pays a parking ticket for his neighbor and later asks her out on a date.

Lilly investigates the 1996 murder of a wealthy divorced woman who was found dead in her ex-husband's indoor swimming pool. The original investigation ruled the death accidental, but new evidence suggests it was a homicide.

In 2002, two kids were shot in front of two different schools on the same day at precisely 8:03 a.m. It's the fifth anniversary of the shootings, and Kat Miller wants to re-open the murders because she feels the cases are connected.

Lilly investigates the deaths of a married couple who perished in 1981 when a supposedly accidental gas-leak explosion set their house on fire. The case is reopened when fragments of a bomb are discovered at the house during renovations. Back at headquarters, Stillman takes care of his 4-year-old grandson.

Lilly investigates the 1964 murder of a 17-year-old girl who was sent by her parents to a home for unwed mothers, where she gave birth to a girl. The next day the teen was killed. The case is reopened when the victim's daughter comes forward, having just learned that she was adopted and that her biological mother was slain.

When a body is found in a dumpster, the team re-opens the 1984 case of a murdered teenage boy who wanted to become a dancer against his father's wishes.

The 1999 murder of a homeless woman, whose body is found at the bottom of a river in a station wagon, is investigated.

A father pushes a registered sex offender off of a building and threatens to kill a different sex offender each day until the cold-case unit solves his son's 1987 rape and murder.

The 1997 murder of a 16-year-old girl high-school cheerleader is investigated after an anonymous confession is discovered in a modern-art exhibit.

The team re-investigates their oldest cold case yet, the 1919 murder of a young woman who was a passionate advocate for women's right to vote.

The 2005 murder of a longshoreman who accidentally became involved in a human-trafficking ring run by the Russian mob.

The 1998 death of a terminally ill man who died months before he was expected to is investigated after a nurse confesses to six so-called mercy killings.

In the fourth season finale, a hostage situation arises when the entire team is held captive while they're investigating the 2006 killings of a family who had just moved into a new house.

Recovered from the shooting, Lilly wants to convince her boss that she's ready to get back to work. The team re-opens the 1994 case of three 10-year-old kids who were beaten to death when Lilly suspects the teens convicted of the killings may have been wrongfully incarcerated.

After a piece of clothing belonging to a murder victim is found, the team re-opens the 1998 case of a high school girl who had a reputation for being promiscuous.

When the victim's younger sister comes looking for her, the team re-opens the 2006 case of a missing Amish girl who was murdered while she was in Philadelphia experiencing the Amish rite of passage called "rumspringa".

The team re-investigates the 1953 case of a talented 19-year-old rock'n'roll singer when new evidence comes forth, suggesting he wasn't killed in the place where his body was found.

The team re-opens the 1989 case of an unidentified Jane Doe when she dies in the hospital, after being comatose since the day she was shot 18 year ago.

The team re-opens the 2002 case of a 14-year-old math whiz whose half-brother exploited his unusual talents: card counting and safe cracking.

When human remains are discovered at the bottom of a well, the team opens the 1938 case of a housewife who went missing the night of Orson Welles' radio broadcast of War of the Worlds.

When the body of a newly missing boy is found in a cargo container along with the remains of three other victims who vanished in 1999-2003, the team realizes they're dealing with a serial killer.

The team re-opens the 1963 case of teenage girl who was then thought to have committed suicide. Now, new evidence leads them to believe the girl might have been murdered for acting and dressing like a boy.

The team re-opens the 1982 case of a well-liked young man who was shot to death after being accused of date rape by several female college students.

The team re-investigates the 1945 murder of a Japanese-American family man who was persecuted in his neighborhood following the Pearl Harbor attack. Meanwhile, Lt. Stillman has decided to retire from the force.

The team re-opens the 1999, 2001, and 2003 pipe bombing incidents that killed two and blinded one victim. The serial bomber is still on the loose and ready to strike again as he missed his latest target.

The team re-opens the 1998 case of a murdered 17-year-old girl when her father is arrested for beating another child.

After traces of blood linked back to a missing teen are found, the team re-investigates the 2006 case of a boy who disappeared from a high school for deaf children.

The team re-investigates the suspected 2007 murder of a bride-to-be who was kidnapped on the day of her engagement party. Lilly and Scotty travel to West Virginia to escort the prime suspect to Philly, and on their way back, they hear his side of the story.

When a severed hand is discovered at the scene of a drug bust, the team re-opens the 1997 case of a convicted criminal who was thought to be on the run from authorities all these years.

The team re-opens the case of a woman who allegedly committed suicide in 1962 when the victim's granddaughter comes forth with evidence that the note found on the death scene -- then thought to be the suicide note -- was not written in the victim's handwriting.

A drug addict mother, who lost her son in an apartment fire in 2005, comes forth claiming she just saw the same child in the park.

The 1973 murder of a college-football star's on the eve of a championship game. The unsolved case is reopened when new evidence suggests he was killed earlier than previously assumed and the victim may have been involved with steroids.

The 1991 death of an inner-city schoolteacher is reinvestigated when new evidence indicates she may have been murdered instead of dying accidentally during a carjacking that got out of control.

The team receives new evidence in a 1964 case which was then though to have been a hit-and-run. Now, a threatening letter addressed to the victim prompts Will and Kat to travel to Mississippi to re-investigate the death of a woman who was secretly involved in giving school supplies for black children.

The 1978 death of a teen roller skater who was found in a ravine is reinvestigated when a new witness comes forward.

The team re-opens the 1951 case of a marine who went missing and never reported for duty after his shore leave.

When a body is discovered in the trunk of a car, the team re-opens the 1981 case of a missing single mother who used to work at a car dealership.

The team re-opens the case of a 12-year-old boy who died in 1969 when the retired detective who originally worked the case receives a new clue -- a toy rocket bearing the victim's name.

Lilly and the team look into a 1989 case involving a Russian opera singer. Vera has a strong recollection of the case being a rookie in the department at the time.

The team re-investigates the 1953 death of a murdered pin-up girl when an old photograph provides important new evidence.

When Dexter Collins, a young activist with a bright political future was found shot to death in 2005, it went down as a drug buy gone awry. Following a new tip regarding the location of the weapon, the police reopen the case and interview everyone from members of street gangs to his opponent for the city councilman seat.

The 1960 murder of a stewardess who was attempting to organize a union is investigated, and the probe uncovers several hostile suspects who strongly resented her.

The team re-investigates the 2007 murder of a mechanic who won $8 million in the lottery.

The team re-investigates the 1988 murder of a young TV reporter. Previously unseen news footage suggests she was on the verge of breaking a huge story about the unethical practices of a plastics company.

When human remains are found in a duck pond, the team reopens the 1967 murder of a brush salesman.

When the mother of a missing team storms into station. The case of a witness protection member is reopened when his body is identified by the missing teen.

The 1976 murder of a teen-aged girl is reopened when her father produces a photo of her and a vicious biker gang.

The team has to cope with their own emotions as they search for the shooter responsible for Jeffries' shooting.

The team suspect a 2004 arson that killed a psychiatrist may have been caused by her former patient.

The team re-investigates the 1958 case of a newlywed real estate developer when new evidence suggests his body might have been moved after he was killed.

The team re-opens the 1999 murder of a Cuban baseball star who fled to the U.S. after being fired from his team.

When the murder weapon from a 1963 case is unearthed, the team re-opens the murder of a pool hustler who was shot the same day President Kennedy was assassinated.

The team re-opens the case of the first ever female cadet in a local military school who was murdered in 2005.

The investigation into the female cadet's murder continues. As the team finds more and more clues, the killer tries to stop the investigation to remain hidden.

With the team investigating the 1966 shipboard murder of a young woman traveling in steerage on a luxury ocean liner who was believed to have committed suicide by jumping overboard. But new evidence indicates otherwise. Meanwhile, the trial of a military academy official who attempted to harm Lilly begins.

The team re-opens the 1995 case of a skateboarding prodigy who lived on the streets.

The 2004 murder of a teen at a juvenile detention center is investigated. The boy was wrongly sent to the facility and was killed before Valens could get him released. Meanwhile, Lilly reconnects with former flame Eddie Saccardo, a narcotics officer.

The 1970 murder of a musician who was instrumental in creating the Philadelphia soul sound is reinvestigated. The victim tried to keep his involvement in the music scene from his strict minister father. Meanwhile, Lilly meets her teen stepbrother, Finn.

The 1944 murder of a female pilot who flew noncombat missions for the U.S. during World War II is investigated. The victim was part of a civilian program that assisted the Army and Air Force. Meanwhile, the man who ran Lilly's car off a road is released from prison on bail.

The 1986 murder of a jockey is investigated after his body is discovered in a mass grave for horses. The victim disappeared shortly after losing a race that he had planned to be his finale before retiring.

The 1991 murder of a 14-year-old girl in foster care who was a promising rapper is investigated. The probe reveals the victim lived in a gang-infested neighbourhood and was recently placed, along with her sister, with new foster parents.

The 1983 murder of a Chinese-American teen is reinvestigated. The case was originally handled by Stillman. The probe reveals the victim's girlfriend was killed by Chinese gang members three months earlier at a festival and that the dead man may have been seeking revenge.

The 1999 death of a high-school debate champion, which was originally ruled a suicide, is investigated after new evidence suggests he was murdered. The probe reveals the victim received a scholarship at a top private school and died shortly after losing a debate at the competitive campus.

The 1980 murder of a minor-league hockey player is investigated. The victim was killed on his team's home rink the night the U.S. hockey team defeated the Soviet Union in the Olympic Games.

The 2005 murder of an Army recruiter who was killed just two days before his scheduled deployment to Iraq is reinvestigated after a soldier comes forward with new evidence.

The 1974 murder of a private investigator is probed after his body is discovered in the cement foundation of a demolished building. The investigation reveals the victim uncovered damaging information about his last few clients and that he hired a tough associate to provide muscle during his final investigation.

The 1983 murder of a graffiti artist who died after spray paint was forced down his throat is investigated. Meanwhile, new details emerge about the person who mugged Valen's mother; and Lilly faces additional legal hurdles thrown her way by Moe.

The 1971 death of a teen aerialist who fell during a dangerous circus performance is investigated. New evidence suggests her fall wasn't an accident.

Lilly and the team attend a colleague's wedding and are persuaded by Jeffries to investigate whether the bride killed her former fiancé two years earlier - just hours after he called off their nuptials.

The 1986 murder of a dock worker who moonlighted as a wrestler is investigated. Meanwhile, Valens follows a lead that could result in the capture of his mother's rapist.

Realizing that the missing Vera has finally hit rock bottom, his worried team members hope that a new twist to a 2006 arson case, which he was secretly obsessing about in recent weeks, might supply leads to his whereabouts.

When ballistics tie a recent murder case of Rush's to a serial killer who was seemingly inactive for 27 years, a tough FBI agent with ties to Stillman shows up to enlist the team's aid in finding the killer who has eluded her for 30 years.

After determining the serial killer's identity - and some of his likely future targets - the team and the FBI work together to apprehend him while trying to locate and protect the people he's preparing to kill.

Rush and FBI agent Ryan Cavanaugh discover their attraction for one another while investigating the 1969 murder of a GI at Woodstock, and Vera helps his married ex-girlfriend, Megan, after sentimental jewelry is stolen from her home.

Rush tries to ignore her father's appeals to give her troublemaker sister another chance after she suddenly resurfaces.

Valens partners with Rush to locate her abducted, drug-addicted sister, while Jeffries tries to bring justice to the case of a murdered teenaged girl that has haunted him for 17 years.