A retired MMA fighter turned trainer juggles keeping his mixed martial arts gym running and keeping his family united.

Identical twins Leni and Gina have secretly switched places for years. But when one sister disappears, both of their lives start to fall apart.

When mysterious wreckage starts falling from the sky, a secretive international agency is tasked with figuring out what it is, where it came from, and most importantly… what it can do. British agent Finola Jones and American agent Bryan Beneventi are partners who have very different styles – she's warm, intuitive and detail-oriented, and he's charming, confident and guarded. But they have no choice but to trust each other as they track down the debris scattered across the Western Hemisphere. Each fragment has unpredictable, powerful and sometimes dangerous effects on the everyday people who find it. Every discovery is also a race against time, because shadowy outside forces seek these objects for nefarious purposes.

In early 1990s Boston, Assistant DA Decourcy Ward forms an unlikely alliance with a corrupt yet venerated FBI veteran, Jackie Rhodes. Together, they take on a case that ultimately changes the city's entire criminal justice system.