When a strange new race, called Klingons, crashlands on earth. The Vulcans finaly allow the Humans to explore space. Their first mission, bring back the Klingon. But space is a dangerous place. Another race, the Suliban, are hunting them, trying to win a temporal cold war, that have yet to occour. Archer apparantly destroys a world, and is transfered to the 31st century where the federation was never created.26 episodes in season. 136 in rank.
Archer, still in the 31st century, must try to recreate history, and make sure the Federation will be formed later in history. And earth is attacked by a drone from an unknown enemy.26 episodes in season. 133 in rank.
The Xindi are creating the ultimate weapon, to destroy the human race, before the humans destroy them. Meanwhile Archer is on his new mission to find the Xindi, and figure out why they attacked.24 episodes in season. 114 in rank.