Thrown into a distant part of the universe, Earth astronaut John Crichton remains caught up with a fugitive alien starship crew. In season four, Crichton and Aeryn find their way back to each other as danger closes in. An uneasy alliance with Scorpius begins to take shape, while the reptilian Scarrans pursue the wormhole knowledge in Crichton’s mind, hoping to use it to rule the universe.