What episode was it where Gus is talking to Juliet and says 'I see everything' then turns around and walks into the door? The scene takes place in the police station in one of the rooms.
你 are thinking of Season 4, episode 12 titled "A Very Juliet Episode". This takes place near the beginning after Gus enters the 拱顶, 保险库, 跳马 of secrets.