Highly intelligent and emotionally distant, Kirsten Clark has an aptitude for technology but never expected that she’d be hacking into the minds of the recently deceased.

A dangerous new drug has claimed the life of a young woman and, while the Stitchers team is looking for its source, they run into Detective Fisher, who is on the same trail.

It’s Kirsten’s birthday and the Stitchers team is assigned to look into a disease researcher’s suicide. When the body begins showing signs that it is carrying a deadly virus, the whole lab is placed under quarantine. The team jumps to action as they search for a way out, racing against the clock as, one-by-one, they come down with symptoms of exposure.

The Stitchers team is on the defense when Cameron and Detective Fisher are targeted in a shooting. Kirsten's stitch leads them to Robert Barbiero, a security expert who has worked with Maggie in the past and was close to Kirsten's mom. As Kirsten follows the clues that Ed Clark left her, she finds unexpected answers to long-held questions.

Kirsten successfully revives Cameron, but finds that stitching into a live consciousness is now causing her to experience real emotions for the first time.

Fueled by his love for Kirsten, Cameron finds a way to bring her back to reality, but it could cost them their relationship. Meanwhile, the Stitchers lab is on lockdown, leaving an anxious Linus unable to check on his father’s condition after surgery. But, as the team prepares to be reassigned for breaking protocol, NSA Director Mitchell Blair surprises everyone by demanding an emergency stitch that yields shocking new information.

When Kirsten wakes up to find that everyone in the stitch lab, except Cameron, is missing, the two search everywhere but only find a series of mysterious clues. Kirsten is forced to confront her own emotions about her relationship with Cameron.

Kirsten’s father Daniel Stinger shows up and Kirsten must perform the most important stitch of her life.