When MIT grad student Liam Cole (Charlie Rowe) discovers an asteroid is set to collide with Earth in 186 days, he joins forces with tech billionaire Darius Tanz (Santiago Cabrera) and the U.S. government to try and stop it - and together they stumble onto the greatest conspiracy never told.

Darius and Liam work to invent a theoretically impossible piece of technology to divert the asteroid, and Grace risks everything to help Darius. Also, Liam heads home to Boston to track down critical research, but finds something shocking instead.

It's a race against time as Darius must accelerate his plan to stop the asteroid before the Pentagon shuts him down. Also, Grace has to make difficult decisions that could have life or death consequences for millions of people, and Liam and Jillian reunite under surprising circumstances.

Darius recruits Grace, Harris and Liam for a dangerous mission, and Jillian confronts Liam about his secret.