User blog comment:Baldo Lleonart/Harry Potter and the Deathly Hallows Part 2 Trailer Analysis/@comment-3518291-20110430023423/@comment-3133928-20110430192140

Harry Potter and the Deathly Hallows Part 2: Differences from the book "Once Harry reveals himself, Voldemort locks Harry up asking how he escaped death, after Harry tells him Voldemort lets him out. This causes their chase around many different places in Hogwarts."

maybe sometime in the "chase" this happen.