Husband and wife Max (Bateman) and Annie (McAdams) have a regular game night with some friends of theirs, including Ryan (Magnussen), Michelle (Bunbury) and Kevin (Morris). When Max's brother Brooks (Chandler) shows up in town and invites the gang to his own game night, they arrive at his place to discover that he's set up an elaborate whodunnit mystery, complete with actors to make the game as realistic as possible. As the game continues, though, the players begin to realize that not all of the people involved are actors, and that the game and real life are intersecting in unpredictable and highly dangerous ways.
Accomplished Russian ballerina Dominika Egorova (Lawrence) struggles to make ends meet as she supports her ailing mother, especially after she suffers a devastating injury that brings an abrupt end to her dancing career. Her uncle (Schoenaerts) recruits her to work as an asset for Russian intelligence in exchange for help with her mother's medical care, and she undergoes training to become a Sparrow, a spy skilled at seducing her targets. When she's given her first target, a CIA agent (Edgerton) based in Budapest, the two of them begin a relationship that threatens the security of both nations.
When his peaceful Stone Age tribe is driven out of its idyllic valley by a Bronze Age civilization led by Lord Nooth (Hiddleston), caveman Dug (Redmayne) challenges the "civilized" people to a high-stakes game of soccer, with ownership of the valley at stake. When he tries to whip his tribe into shape and teach them the game, though, Dug fears that Nooth's highly competitive team will effortlessly wipe the floor with them, leaving them exiled from their home valley until the end of time.