An emotionally damaged ex-police detective goes back on the job to investigate a serial killer after her seemingly happy marriage falls apart.

1. Episode 1 46m After her once-happy marriage dissolves, a former detective grapples with jealousy and anger while returning to work to hunt down a serial killer.

2. Episode 2 46m Marcella is desperate to remember what happened at Grace's. Meanwhile, she sees patterns that convince her the killings are linked to her old case.

3. Episode 3 46m The team learns of Marcella's ties to Grace. Jason's affair comes to light at DTG. Peter Cullen remains Marcella's focus in the Grove Park murders.

4. Episode 4 46m There's an unexpected break in the Grove Park murders, but not everything adds up. Marcella goes on her own to find out details about Grace.

5. Episode 5 46m Marcella plays a cat-and-mouse game with Peter Cullen. New details of Grace's case lead to shocking connections. Jason's mistake could prove fatal.

6. Episode 6 45m The outcome of one of the cases sends Marcella over the edge. Tim suspects a suicide was really murder. A past tragedy haunts both Jason and Marcella.

7. Episode 7 46m Yann is now a prime suspect, but Marcella has her doubts. Tim and Marcella grow closer, while Tim's investigation into Barnes's death unsettles Jason.