Miami, 1991; when his bloodthirsty urges can't be ignored any longer, young Dexter Morgan must learn to channel his inner darkness as he transitions from student to avenging serial killer with the guidance of his father, Harry.
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.
In the fallout of a SWAT raid gone wrong, Dexter closes in on the child kidnapper; 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.
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; Miami Metro closes in on suspects in the child kidnapping.
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.
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; first, Dexter must survive a double date with Deb and her new boyfriend.
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.
Dexter targets a retired mob hitman; Harry works the gruesome murder case of a ten-year-old boy; Deb sneaks into a nightclub with Sofia and meets an exciting new friend.
Dexter goes after a loan shark with ties to Batista; Deb throws a party to win the favor of her volleyball teammates.
Dexter adjusts to his new job as a forensics intern at Miami Metro; Deb lashes out at her dad by engaging in petty criminal behavior.
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.
