Despite never having worked on a homicide before, Faith and Cerys take over Madlen’s case and end up on a collision course with Tom. Meanwhile, DI Breeze pressures Evan for information about Faith.

Faith warns against letting Madlen testify, but when Faith is called away for a family emergency, Cerys is forced to put Madlen on the stand. As the trial climaxes, Faith tries to keep it together while DI Breeze continues his campaign against them.

After Madlen’s sentencing, Faith vows to find William’s killer, but first she must contend with the other crises in her life. Evan’s approaching early release brings conflicting emotions for the family, and DI Williams shares shocking new evidence with Faith.

As Steve’s daughter recovers in the hospital, Gael ramps up the pressure on Faith to close the deal with Corran Energy. Evan tries to adjust to life at home, but DI Breeze insists that Evan wear a wire to his next meeting with Gael.

Gael manages to turn the tables on the Corran Energy deal, but she refuses to release Faith from her debt. Faith gets closer to identifying the mysterious woman in the photograph, but what she finds may change her relationship with Evan forever.

Eighteen months later, Faith and Evan’s divorce battle goes from bad to worse as Evan argues for shared custody. Cerys urges Faith to help her with a complicated case involving a local man, Mike, who is fighting for his sick son, Osian, to have a controversial brain surgery. Steve reluctantly takes on a dangerous job, with disastrous consequences.

Faith reels from the fallout of seeing her mother, Rose, again and gets an even bigger shock when Rose takes legal action. Alys acts out, and Lisa faces a turning point with her alcohol addiction.

Steve asks Faith to corroborate his alibi for the night of the break-in. As Faith preoccupies herself with Osian’s case despite being fired by Mike, her divorce proceedings take a toll on her kids, and Alys gets involved with a political demonstration.

After the judge’s unfavorable ruling, Faith urges Mike to take the case higher up the chain to the Court of Appeals. As Faith prepares for the legal fight of her career, Rose blackmails Faith into doing a job. In London, Faith reconnects with an old friend.

Mike is shocked when Osian’s tumor is deemed inoperable. Faith and Steve are flying high after their night together, but their bliss is short-lived, as Evan becomes more and more obsessive and Steve disappears from his cabin.