They killed us, and destroyed everything on board ship including the time drive which meant that there was no time drive for them to have in the future to bring back into the past to destroy the future of their past selves in the present! Put simply, they killed themselves by killing us because once we were dead, it was impossible for us to become them in the future and return in time to kill ourselves in the past even though it was the present!”
— Dave Lister, Red Dwarf, Tikka to Ride
