 Lister then goes back to Cassandra's chamber, telling her that he doesn't like the idea that his entire future is already picked out, and plans to prove he can make his own decisions by refusing to kill her.As he exits, he takes chewing gum out of his mouth and idly sticks it to the wall.It lands on the fan, turning it on, and ricochets to a glass of scotch; the scotch spills and lands on Cassandra's power wire, inadvertently killing her.