Continuity mistake: In the restaurant having dinner Rene's pearl necklace starts untwisted then twists and later untwists. To do this that necklace would have to be unclasped and manually twisted.
Character mistake: Thomas rips off his one glove as he makes his escape but then grips the bottom edge of the security door to slide under it. Smooth metal door would leave perfect finger and palm prints. I doubt detectives would miss prints on a door that was normally recessed away from the public. His prints may not be on file but would be easy to obtain once he was under suspicion. (00:19:20)