Season 4: Episode 78: Cliff's Mistake
The Huxtables' neighbor, Jeffrey, requests that Cliff return his power drill. Cliff searches the entire house three times, but cannot find the drill anywhere. Cliff apologizes to Jeffrey, who explains the sentimental value of the drill (which belonged to his father) and rants and raves about how he can no longer trust Cliff. Cliff offers him a new drill, which he angrily refuses. Cliff believes that Jeffrey is overreacting, but Clair points out that he has acted the same way at times. When she suggests giving Jeffrey the new drill for Christmas, Cliff has an inspiration. He remembers that he put the drill in a box marked "Christmas lights" to discourage the kids from messing with it. Theo, Vanessa, Rudy and Kenny put together a haunted house in the basement for Halloween.