One last mystery holds the key to saving the world, and Grace must choose how she spends her final days.

Grace and Darius slip off to Russia behind Harris’ back in an attempt to stop a potential nuclear conflict. Also, Liam seeks solace with Amanda.

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.

In order to prove to Harris and Grace that he’s not a traitor, Darius must reveal one of his most closely guarded secrets. Also, Liam helps Jillian adjust to her new job at Tanz.

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.

Grace embarks on a dangerous mission, and Liam and Darius’ relationship is tested.

A stand-off at the COPE compound leads to tragic results

The government’s final plans for a doomsday scenario set in motion a surprising chain of events for Grace, Darius and Harris.

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

Grace and Darius seek answers from the President and Harris discovers deadly secrets.

Darius, Grace and Harris join forces to prove the president was murdered. Also, Grace tells Zoe the truth.

Harris, Grace and Darius must topple the illegitimate government, and Darius makes final plans for the ark.

After a nuclear incident, the secret of the asteroid becomes public, setting the world on a dangerous course. Darius, Grace, Liam and Harris must adapt to new roles in an ever-shifting landscape of fear and civil unrest.

Darius, Grace and Harris uncover the darkest secret yet, and Liam reconnects with Jillian.

Darius forms a dangerous alliance in order to destroy the dark money forces of Q17. Also, Grace takes action when surprising news jolts her world.

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

Framed for murder, Darius and Grace must try to escape from Russia, and Liam tries to convince Jillian to come back to Tanz.

Grace narrowly escapes a deadly assassin and Darius and Liam forge unlikely alliances.

Grace and Harris must forge an alliance when their children’s lives are in jeopardy. Also, Liam presents Jillian with an unusual proposal.

Desperate to defuse a nuclear standoff, Liam receives help from an unlikely source. Also, with Darius missing, Harris and Grace take matters into their own hands.

While Darius works to discover who killed his friend Lazlo, he is forced to reckon with his past, and Liam discovers who’s been selling secrets to the Russians.

Darius and Grace must forge an emotional détente to get international cooperation. Liam meets a new scientist who has a mysterious past.

Grace is asked to lie under oath. Darius tasks Liam with a dangerous mission. A shocking act of violence plunges the nation into chaos.

Darius and Grace’s relationship is tested, and President Mackenzie attempts to bring the fractured country together while the hacktivist group ReSyst issues a deadly edict.

Grace forges a dangerous alliance with Claire’s brother, Alonzo. Also, Harris and Darius must work together to face down Bennett’s forces