Black Christmas (2006)

Continuity mistake: At the end, while Billy chases Kelli, Kelli knocks over a cart of surgery supplies, spilling the material forward. However, a few shots later, Billy is shown picking a scalpel up from the small tin pale, which slid ahead of Kelli. So how could Billy have picked up the scalpel if he was behind Kelli?

Dana Mathis: Are you high? It's freezing out there.

Question: If Billy's mom hated him and her husband then why not leave? That and why not kill Billy instead of imprisoning him?

Rob245