Team Scorpion must defy the orders of a foreign government after they retrieve an asteroid from space containing DNA strands that could have deadly consequences once exposed.

On Thanksgiving, Team Scorpion's new neighbor, Florence, joins them at sea on a mission to destroy a floating island of trash, but her flawed contribution leaves her, Walter and Happy stranded on the quickly dissolving island. Also, Toby works with Cabe to uncover the details of his father's death that he has suppressed since he was a boy.