The Fat Lady's Portrait is Slashed by Sirius Black
Pages 159-161
After the Halloween feast, the Gryffindor students return to Gryffindor Tower, only to find the entrance blocked. Percy Weasley pushes through the crowd to find that the portrait of the Fat Lady has been slashed, and she is missing. Peeves reveals that she fled after refusing to allow Sirius Black into the tower.
