My Freaky Valentine: Part 2 - S4-E9
Continuity mistake: When Joey sets a monster face down in defence position, he places the monster card in the second monster card zone on his duel disk. Then there is a brief scene of Devlin checking which doors are locked, but when the scene cuts back to the duel, the face-down monster card is now placed in the fourth monster card zone on his duel disk. (00:12:05 - 00:12:29)