Plot hole: Amanda Haynes is Lacey Duvall's murderer, however in the opening scene she was kissing Patrick Haynes at the party downstairs at the exact time Lacey fell into the pool. She could not have pushed Lacey upstairs. (00:01:16 - 00:41:29)
Continuity mistake: When Gil and Catherine catch the couple in the bedroom, they are all sitting in the living room. Amanda is drinking a soda and it is about half full. Gil then asks for the straw. When we look at the soda again, it's full.
Answer: The episode on CSI:NY was called "Love Runs Cold" and first aired on October 4, 2006 (Season 3, Episode 3) and involves the investigation of a model found stabbed to death by an ice dagger.
OneHappyHusky