Five years after retiring from the CIA, Steven and Samantha Bloom are thrust back into the espionage world when a good friend goes missing. Despite their initial hesitation, they discover it's what made them fall in love with one another in the first place.

When an informant claims to have information on a code-breaking device that would compromise the identities of every agent in the CIA, Shaw sends Steven and Samantha to Berlin to verify the man's claims. As the team travels throughout the city, they are surprised to learn that the device isn't as it seems. Amidst the danger around them, Steven and Samantha struggle to find the balance between being partners and a married couple while in the field. Back in Los Angeles, Lizzy connects with a man while catering his father's funeral.

When a vital CIA hard drive goes missing, Steven and Samantha must travel to Dublin, Ireland in search of a prisoner who holds the key to its location. Following leads, their mission takes them to England. Meanwhile, Samantha begins to question whether or not she and Steven should speak about their pasts, and Lizzy invests time and money in the catering business.

Steven and Samantha are to find Shin Won—a North Korean physicist responsible for inventing a device that can change an object's state of matter—and facilitate his defection. What should be an easy mission in Geneva, Switzerland becomes more complicated by the minute when Shin Won refuses to come to the U.S. unless they get his daughter out of North Korea. Meanwhile, Samantha misses Lizzy's milestone celebration.

After renowned weapons dealer, Xerxes, hides the formula to a dangerous and lethal biological weapon in a painting, Shaw assigns Steven and Samantha the task of traveling to Tuscany to secure the painting and capture Xerxes. When the assignment requires Samantha to assume a previous cover and partner with Steven's enemy, Clive, the Blooms learn that teaming together is not as easy as they thought. Meanwhile, Hoyt's attraction to Clive's assistant proves to be instrumental in finding the culprit.

Steven, Samantha and Leo get orders from Shaw to take on a mission in Lima, Peru where an assassination plot has been orchestrated against President-Elect Alberto Loya. When Samantha gets too emotionally invested, she puts the whole mission at stake and her own life in danger. Elsewhere, Lizzy caters a party for one of Samantha's college friends.

When a plane disappears off the radar and its pilot is nowhere to be found, it's up to Steven and Samantha to locate the man and the dangerous bomb he has with him. Traveling to Russia, the Blooms team with Hoyt and meet with some unexpected challenges in their quest to complete their dangerous mission. Meanwhile, Shaw wonders how much time he has left before the Blooms become suspicious of his underlying motives, and Lizzy takes charge with a client.

When Leo wakes up in a hotel in Mexico with a dead woman next to him and no memory of what transpired, Steven, Samantha and Hoyt travel south of the border in hopes of putting the pieces together to prove Leo's innocence. The stakes get even higher when Shaw unexpectedly arrives with news of a dangerous terrorist on the loose.

When American currency engraving plates are stolen from an armored truck, Steven and Samantha must recover them before the terrorist who stole them counterfeits American money. Traveling to Croatia, the situation gets complicated when the Blooms find themselves working together with Steven's estranged brother Gary. Meanwhile, Leo helps Lizzy make a decision about her future.

Just when Steven and Samantha have settled into their romantic Greek vacation, Shaw pulls them away to lend their assistance to an escalating situation in Tel Aviv, where terrorists have seized a hotel and taken hostages. Going undercover with help from Hoyt, the duo soon realizes their mission involves much more than they were told.