A Boston family finds out that one of its own may be behind a series of infamous grisly killings. After tragedy strikes the Hawthornes; Cam, Tessa and Alison seek answers about the silver bells.

Tragedy strikes the Hawthornes. Cam, Tessa and Alison look for an explanation for the silver bells they found. Garrett plans to expose a family secret. The police inquiry into the `Silver Bells Killer' sends Brady on a hunt for DNA.

Police focus their investigation on the Hawthornes. Cam wants to erase his past while Garrett embraces his, and the behaviour of one of Alison's siblings complicates her campaign.

Police focus on the Hawthorne family's possible connection to the 'Silver Bell Killer'. A death on the Hawthorne property turns into a solid lead for Brady. Garrett gives into temptation.

Cam experiences hallucinations that make him question his involvement in a gruesome crime, while Madeline leaves town to confront the sender of a cryptic message.

The Hawthornes turn on one another after they are publicly implicated in the SBK case, forcing them to stay at the house to avoid the media. Meanwhile, Garrett brings Christina on a camping trip that takes a dangerous turn.