In 2176, the crew of the deep space transport S.T.C. Nicola Tesla must fly a mysterious passenger from the Uranus System to the Neptune moon Triton. The crew becomes aware of an imminent cosmic catastrophe that will force humanity to leave the solar system and is working on a rescue plan.
On Triton, a small remote research station, the Brennagans are concluding their tour of duty. Dr. Jenna Brennagan wants to stay and finish her research on extraterrestrial lifeforms, but her husband Gordon is happy to go back home to Earth.
On the way to Triton, the Tesla is in danger of being hit by a high radiation solar storm. The mysterious passenger steers the ship out of the danger zone, but the ship’s fuel reserves are depleted as a result. To the horror of the crew, the return journey has become impossible.
At the same time, Gordon is injured in a sudden eruption of a cryo-volcano. His wife Jenna must hurry to save him.