A decoded tattoo leads the team to a mysterious cache of dolls which turn out to be vehicles for biological weapons being sent around the world and now to the FBI. Jane exploits the fear of the weapons to advance her own plan to recover Shepherd.
The murder of a best-selling true crime novelist sends Jane and the team on a hunt for a serial killer detailed in the author's final manuscript, which also features lightly fictionalized versions of the FBI team.
Roman's clues lead to a billionaire hypochondriac with stem cells that could cure Jane, who is now on her deathbed. Patterson and Rich offer to trade the Book of Secrets for the stem cells -- but first they'll have to get it.
Jane and Weller's romantic getaway is cut short when the team must stop Madeline Burke's plans to blow up a building and crash a plane that turns out to be more than the average commercial airliner.
Patterson's father, Bill Nye, returns for a case that pits the team against a pestiferous foe. Zapata goes rogue with an old friend. Jane and Weller continue their search for the hooded figure.
The team discovers an international conspiracy when a deadly weapon is stolen, Jane supports Weller when someone from his past dredges up painful memories, and Patterson and Rich contend with their newly released hacker accomplice.
A horrifying and vengeful villain threatens the FBI. Weller considers his priorities. Zapata and Reade try to navigate their living situation. Patterson explores a budding interest.
The team sets out on an international mission to stop an attack from spreading. Madeline attempts to turn the tables as internal conflict threatens relationships within the team.