The fourth season of MACGYVER premieres 18 months after the Phoenix Foundation was disbanded and our heroes were stripped of their high-level clearances. MacGyver (Lucas Till), Riley (Tristin Mays), Desi (Levy Tran), and Bozer (Justin Hires) have all turned in their secret agent badges for run-of-the-mill day jobs. However, when Russ Taylor (Henry Ian Cusick), an eccentric billionaire with a shady past, comes to them for help stopping an imminent attack, they turn to Matty (Meredith Eaton) for assistance, hoping that she will join them and realise they must get back in the game without the resources of Phoenix. This launches Mac and team on the trail of a centuries-old apocalyptic conspiracy determined to save humanity from itself.