Jake Rizzo, a detective, is chosen by a Chinese savant to be the caretaker of his grandson, Ernie Lee, a kid with a penchant for Martial Arts.
Ernie runs away from home when his relationship with Jake hits some rough spots. Ernie disappears after Rizzo blows up at his overzealous attempts at interior decorating.
Jake bakes a cake but can't shake a stakeout to attend an open house at Ernie's school.
Rizzo responds to annoying neighbors and the city's crime problem by considering a job in a small town.
Ernie's concerns about expensive merchandise in the house and Rizzo's secrecy seem justified when Internal Affairs takes them both into custody.
Ernie saves a raggedy stranger from a pair of toughs, then brings him home.
When Ernie performs a heroic act, Rizzo tries to shield him from the publicity---but he does permit one appearance: a benefit concert with El DeBarge (who sings "Thrill of the Chase").
Erenie gets jealous. He is worried that Rizzo's new romance means that Ernie won't be able to be friends with Patricia anymore.
Ernie's trials with a Rambo-like bully soon pull Rizzo and the bully's father (Nicholas Pryor) into the fray.
Romance is in the air for both Rizzo and Ernie, which means Rizzo has to find a way to explain the birds and the bees to Ernie.
Rizzo braces for what's sure to be a trying visit from his mother (Magda Harout); Ernie goes along with his karate coach's wishes that he alter his style.
Ernie's attempt to teach senior citizens to defend themselves against muggers may bring a lawsuit against Rizzo after one of Ernie's pupils applies what he's learned.
Rizzo agrees to house the grandson of Sabasan's friend, who's waiting to meet his adoptive family, but the "kid" proves to be an irrepressible 29-year-old whose idols are TV cops---and Rizzo.
Ernie makes the soccer team, but he's overcome with guilt because he used his martial-arts skills on a player in the tryouts.
Ernie is suspicious of the goings-on at the neighbors' house, and winds up in jail after he and a friend are caught breaking and entering.
Jake's promotion to a desk job gives him more time for Ernie---but all this "quality time" is driving Ernie crazy.
Rizzo is shot by an ex-con and Ernie identifies the suspect as the same man who entered their apartment posing as a gas-company worker.
Ernie wonders if he's doing the right thing by keeping quiet about his math teacher's problem with a bookie's debt collectors.
Ernie is tracked down by his aunt and uncle, and Rizzo (Gil Gerard) fears it will mean an end to his custody.
Ernie and his pals form a secret club and stumble onto a stash of loot belonging to hoods.
Rizzo leads Ernie's scout troop on a hike in the woods---where he discovers an auto chop shop.
Ernie's rival in a medieval-combat game unwittingly leads Ernie and Rizzo into a burglary ring's underground hide-out.
Ernie learns that a schoolmate and his father cannot read and they're being victimized by a loan shark.