While the Hendersons prepare for Harry's first birthday party, they recall some of their memorable moments since his arrival.

While on a camping trip with his son and his co-worker, George is nervous because his co-worker keeps on playing pranks and later mistakes Harry for a monster.

Sarah is chosen to sing at the school dance with a new student but hesitates when she learns that he's blind.

Nancy welcomes the arrival of her pregnant sister, Emily, unaware that another arrival is soon to follow.

Harry is home alone and left to the fate of two burglars who think a Bigfoot might draw a big reward.

It's Halloween and Harry finally has a chance to get out. However, the Hendersons' neighbour, who is allergic to animal hair, becomes suspicious of Harry's "costume."

While George competes with an obnoxious co-worker for a promotion, Nancy's brother Brett moves in at home and is forced to contend with Harry.

George examines his life after he's trapped in a steam room and, in a heat-induced delirium, sees God. He decides to quit his job.

Brett thinks a primitive mask can cure his ailing love life by casting a spell on Darcy's Swedish au pair Uma, and it seems to work; but his date with her is spoiled by Harry, who is strangely obsessed with the mask as well.

When Harry sets Ernie's pet parrot free, George and Nancy go shopping for a quick replacement.

Angered at the foul attitude of Ernie's baseball coach, Nancy meets his challenge and strikes out on her own as a coach.

The Hendersons suspect that all that glistens is not gold but their missing silver when Brett suddenly comes into a large sum of money.

Harry scores high on Ernie's IQ test, which changes the way everyone relates to Ernie especially when his teacher Ms. Hall comes to visit and encounters Harry.

The Hendersons are shaken when Harry, fearing impending danger, traps them and a menagerie of forest friends inside their home.

In a case of mistaken identity, a baby is left on the doorstep with a note claiming that Brett is the father.

Sarah tells her boyfriend about Harry and jeopardizes the Hendersons' secret, and her love life, when she invites him to dinner.

Nancy moonlights as an aid to a foreign official and suspects his possession of a chimpanzee is on the dark side of the law.

Harry's friendship with Brett, and George's interview with a beautiful author, set off a wave of jealousy in the Henderson household.

George tries to help his cousin, who broke the law trying to save a polluted lake and its fish population.

A businessman offers to buy George's magazine but the buyer's vision of yellow journalism makes George see red.

Darcy discovers the Hendersons' secret and her parents, who doubt her story, send for a psychiatrist.

A tabloid prints stories about a dangerous Bigfoot and turns the Hendersons' public life into a nightmare.

Nancy takes a seat as vice principal at Sarah's school, which doesn't sit well with Sarah and Lorraine.