Devastated by the apparent loss of Jemma Simmons, Leo Fitz risks everything to rescue her. Agent May re-joins the team-only to discover a terrible truth about her ex-husband, Dr Andrew Garner. Meanwhile, after the release of Terrigen, the U.S. government creates the ATCU (Advanced Threat Containment Unit) to monitor emerging Inhumans. But the programme is actually a smoke screen for the sinister machinations of Hydra's leader Gideon Malick, who joins forces with treacherous ex-S.H.I.E.L.D. agent Grant Ward. The resulting carnage spurs Coulson to exact a revenge that will ultimately backfire, unleashing apocalyptic consequences in the form of a terrifying alien entity known as Hive. To help combat this threat, Agent Daisy Johnson organises a small band of Inhuman "Secret Warriors", not knowing that she will soon meet her match and once again be forced to make a heart-breaking sacrifice.