Young Dexter Morgan struggles to keep his urges in check while navigating life with his father, Harry, and sister, high-school senior Deb. After Harry has a health scare, Dexter realizes it may finally be time to fulfill his destiny.
Dexter adjusts to his new job as a forensics intern at Miami Metro, as Harry returns to work after his medical leave. Deb lashes out at her dad by engaging in petty criminal behavior.
Dexter goes after a loan shark with ties to Batista, as Harry is told to keep an eye on Maria Laguerta, Miami Metro's newest homicide detective. Deb throws a party to win the favor of her volleyball teammates.
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.
Deb sneaks away for a trip with her mysterious boyfriend. Dexter is tasked with finding her. Harry and LaGuerta travel to Tampa to look into a potential serial killer on the loose, while Miami Metro closes in on suspects in the child kidnapping.
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.