Far from land, Arthur Wilde and his team of scientists celebrate the culmination of decades of research: a solution to climate change. Then, a gruesome murder – eerily similar to Wilde’s South Pole nightmare – occurs onboard.

With Charlie locked up, Amy brings lingering doubts to Wilde, confirming his greatest fears. In the U.K., Olivia and her sister are attacked while plotting their revenge.

After breaking out of his confinement, Charlie cuts the ship’s power once again and embarks on a murderous rampage. As Olivia finds herself one step closer to Rachel, Gloria pulls away from Wilde.

After another scientist turns up dead, the mole reveals their true identity – and asks for a favor in return.

As the Alexandria threatens to explode, the remaining scientists jump ship and onto the only life boat – putting them face-to-face with the real killer.