Songfacts®:

• "In Too Deep" documents Sum 41 frontman Deryck Whibley's relationship issues. He and his girlfriend are ever problematic, but they cannot bring themselves to end their partnership: "The faster we're falling, we're stopping and stalling, we're running in circles again. Just as things were looking up, you said it wasn't good enough, but still we're trying one more time."
  
  During the chorus, Deryck metaphorically links the relationship to drowning, claiming he is "too deep" into the relationship, before adding he is trying to keep himself from "going under."
• The video was directed by Marc Klasfeld, who was at the helm for their first video, "Fat Lip." In a parody of the diving scene from the 1986 Rodney Dangerfield film Back to School, sees Sum 41 compete against Speedo-wearing jocks in a diving competition.
  
  The video features real Sum 41 fans - they put out a call and took the first 400 that showed up at the City Of Industry Resort Swim Center in City Of Industry, California. Drummer Steve Jocz told MTV that the band like to cast actual fans in their music videos: "When we did our first video, people said the kids looked so real, and that's because they were real, So we decided we want to have our fans in every video we do. Videos are for fans to see, so you might as well have them in there, [rather] than some hoochie-coochie mama."
• Deryck Whibley often performed this track with his wife at the time, Avril Lavigne, during her 2008 "Best Damn Tour."
• Steve Jocz told Songfacts that "In Too Deep" is one of Sum 41's four most popular tracks: "Well, that's one of them. That one, 'Fat Lip,' 'Still Waiting,' 'Hell Song.'"
• "In Too Deep" was penciled in as the first single from Sum 41's debut album, All Killer, No Filler, but when they came up with "Fat Lip," they moved that one to the leadoff spot and released "In Too Deep" next.