“200” is episode six of season ten of Stargate SG-1.
This is the 200th episode and apparently Mitchell is also just going to step through the gate for the 200th time, hence the title. Martin, last seen in “Wormhole X-Treme”, is shooting a feature length version of the short-lived TV show of the same name that appeared in that episode. He wants help, and, due to a gate malfunction, SG-1 are stuck trying to help him out.
Like “Wormhole X-Treme”, this episode is tongue in cheek. When the lead actor of the film quits, Mitchell suggests they bring in a new lead character to replace him and Sam suggests getting him on the phone every once in a while. Which was pretty much what was done with Jack O’Neill. Vala suggests something rather like Farscape (which she and Mitchell – the actors anyway – both appeared in prior to this) and the clip she envisages has the SG-1 people playing the roles of the Farscape characters.
Jack O’Neill appears, and General Hammond gives a voice over. Another rather unserious episode where sometimes you don’t know whether what’s happening is happening in the actual episode or in the brainstorming. Not sure this was really the best idea for a milestone episode, and this was also a bit too self-referential, especially at the end.