Episode 424

"Break through Crimson Hell! Buggy's great Uproar Plan" is the 424th episode of the One Piece anime.

Short Summary
Buggy and Luffy fight their way through to the entrance of Level 2 by going through Level 1, Crimson Hell, where the lowest ranking criminals are held. To convince Buggy to help Luffy get to Level 2, he gave him his bracelet (which he got from Nami's treasure), which apparently was a clue to a treasure Buggy was looking for.