While the entire Boston Police Department searches for Alice Sands, the team investigates a car crash that isn't all it seems. In the midst of this, a new romance blossoms.

When a mailman is killed, the team must work with a brash, eccentric Postal Inspector, who believes the mailman's murder is part of a larger conspiracy. Maura continues to struggle with the ramifications of her injury and Angela intervenes when she discovers Korsak has gotten Kiki a terrible birthday present.