Winchester "Che" Cook is a friend of Summer Roberts who attends Brown University with her.
Che Cook was the driving force behind Summer's left wing activism. When he and Summer break into a science lab and are interviewed by the Brown board, he blames all his illegal activities on Summer. As a result of Che's actions, Summer was suspended from Brown. Che later feels guilty and regretful for his actions and travels to Newport to ask her forgiveness. Later it's discovered he is actually extremely rich - his father owns a pharmaceutical company. In "The Chrismukk-huh?", he appears in an alternate universe when Ryan Atwood and Taylor Townsend are in a coma. In this universe, he took what would have been Ryan's spot for admission at Harbor, and was engaged to Summer Roberts, and having an affair with Julie Cooper and any woman he could get his hands on.In this universe, he wasn't an activist, as he is in real life. Later, in an attempt to repay Summer for her forgiveness for his misdeeds, Che tries to help Seth Cohen feel harmony with himself and takes him to the woods to connect with his spirit animal. During this trip, Che is convinced by a dream that Seth is his soul mate. Che attempts to test this idea in "The Groundhog Day" with mixed results eventually winding up with the pair in prison. However, Che realises that Seth was not his soul mate, it was actually the environmentalist girl who is placed in the cell next to them. Together, Che and his soul mate leave Newport.
- His last name, Cook, is revealed as the officer announces his release.