"The Blunder Years"
"Original Air Date: 12/09/01"
Homer takes the family to see a hypnotist show. Homer becomes hypnotized and it brings back a repressed childhood memory from when he was 12. Marge uses her Yaqui Tea Set to help bring back the memory. Homer recalls a hiking expedition with Lenny, Carl, and Moe. That day they were going to go swimming in the old quarry. Homer was the only one that went in the quarry and while he was in there he discovered a corpse in a drainpipe. Homer never told anybody about it until then. Soon, the Simpsons family is out at the old quarry to look for the body because they think murder is at hand. Once down at the old quarry they find the body again and follow the drainpipe Homer said it came down. It led up to Mr. Burns' office. Mr. Burns said that the body belonged to Waylon Smnithers Senior, Mr. Smithers' father. He showed them a tape of how he died, which wasn't from a murder, but radiation from the nuclear plant. Mr. Burns merely shoved Waylon Sr.'s body down the drainpipe.
This is Episode #274 is The Simpsons' series. It is Episode #5 in Season 13.