The timestream was changed by sending a Doomsday Machine back in time. There, the Doomsday Machine destroyed several planets, manufactured more Doomsday Machines, and began what is now known as the Doomsday Wars. Captain Kirk, in command of the USS Farragut, is sent back in time to prevent this from happening and save the future. Written by
Did You Know?
[about the Guardian of Forever
You have studied it, of course?
Not as much as we'd like. To tell you the truth, we're a little afraid of it.
That is wise.