Dexter targets a retired mob hitman (who may still be killing), as Harry works the gruesome murder case of a 10-year-old boy. Deb sneaks into a nightclub with Sofia and meets an exciting new friend.

After a kill goes wrong, Dexter is grounded by Harry. Deb deepens her relationship with Gio, and bonds with her brother on the anniversary of their mother's death.

Miami Metro is shaken by a kidnapping that hits close to home, as Dexter sets his sights on a killer that slipped through the cracks of the justice system. But first, Dexter must survive a double date with Deb and her new boyfriend.

Dexter needs to find a new hiding place after his most recent dumping ground is blown. Harry and LaGuerta pitch a controversial theory to Spencer, as the hunt for a missing child continues. Deb gets in trouble for an outburst in volleyball practice.

In the fallout of a SWAT raid gone wrong, Dexter closes in on the child kidnapper. Meanwhile, Deb goes to work with her Dad... and sees Miami Metro in a new light. Harry digs deeper into the serial killer case but keeps his theory from LaGuerta.

Dexter races to find the missing kidnapped child before it's too late. Deb visits her godfather in the hospital and rethinks her future. Harry comes face-to-face with a serial killer... leading to a shocking result.