The episode starts with all the characters dead having been defeated by an unknown enemy. We see Trance Gemini still alive having guilt about being unable to prevent the deaths of her friends and colleagues. Trance is tending to a bonsai tree, a very small tree that people trim and cut down to size. Trance is able to rewind time and affect the course of history.
Through making small changes to the timeline, Trance is able to prevent the death of a character such as Seamus Harper by getting Dylan Hunt to order him not to confront the intruder.
Although Seamus is saved, the intruder turns up again later and kills Rebekah Valentine on the bridge. Even with his heavy weaponry, the intruder is no math for Tyr Anasazi and neither is Rommie
The Intruder, all dressed in black is revealed to be travelling backwards in time by Rommie. Eventually after the day is played over and over again, Dylan Hunt encounters the intruder in the engine room and using his force lance as a pole knocks the Intruder into the engine thus killing him.