After navigating a possible retrial, a 73-year-old Michael confronts a life-changing decision. Meanwhile, Martha and Margaret each share long-buried truths, and Sophie comes to terms with a revelation.

After a body with similar injuries to Kathleen's turns up at the county morgue, Sophie continues her quest to uncover what really happened to Kathleen. Meanwhile, Martha decides to dig into her fraught past, despite pushback from Margaret.

In 2006, Sophie pursues a far-fetched new theory about the night of Kathleen's death. Then, in 2017, Michael grapples with compromising his principles in exchange for his freedom.

In the aftermath of the verdict, the Petersons struggle with the court's decision, and Michael finds solace in an unlikely friendship from thousands of miles away.

After an unexpected homecoming, a critical discovery rocks the Peterson household. Michael's fate hangs in the balance as the trial ends.

As the DA's office attempts to solidify their case, shocking new details surface about Michael's past that threaten to derail the defense.

While working on his defense, Michael considers an opportunity to tell his story in a documentary. Then, after learning shocking information about her stepfather, Caitlin wrestles with doubts.

In 2001, author and aspiring local politician Michael Peterson is charged with murder after the suspicious death of his wife Kathleen.