What happened to Deb and Dexter's mother in Dexter: Original Sin

WARNING: SPOILERS ahead for Dexter: Original Sin episode 1.

THE Dexter prequel series Dexter: Original Sin includes Doris Morgan, Dexter's stepmother and Deb's biological mother, in a tragic flashback scene in its pilot episode. Developed by New blood creator Clyde Phillips, the prequel series chronicles a post-college Dexter as he embraces his “dark passenger” through the guidance and teachings of his adoptive father, Harry. Dexter implements Harry's code to satisfy his violent urges while ensuring he will never be caught.

After Michael C. Hall reprized his iconic role as the charismatic serial killer vigilante in 2021 Dexter: New Bloodhe returns as Dexter's inner voice and narrator in the prequel series. The series takes place in Miami in 1991, when Dexter begins his career at Miami Metro PD. Dexter: Original Sin it will likely cover some predicted deaths that are already established in Dexter lore. Another upcoming Dexter series, Dexter: Resurrectionexpected to be released in summer 2025 with Hall also scheduled to return.

Doris Morgan died of cancer when Dexter was in high school

Dexter was 16 and Deb was probably in high school

Doris Morgan died of cancer when Dexter was still a teenager in high school, meaning Deb was likely in high school. Not much information is known about Doris Morgan as her character is almost never mentioned in the original series and has so far only been included briefly in the original series. Original sin debut episode. Dexter didn't seem to have a very close relationship with Doris but Deb was certainly old enough to have known her mother before she passed away.

Doris Morgan is played by Jasper Lewis in a flashback scene in Dexter: Original Sin episode 1, “And in the beginning…”. In what is one of the biggest backstory reveals of the premiere prequel episode, Harry and Doris lost a child who drowned in their backyard pool. It's unclear how old Deb was when this happened or if she was still alive at that time. Harry and Doris took Dexter in even after Harry had an affair with Dexter's mother, Laura Moser.

Did Dexter's adoptive mother know about Harry's code?

Harry probably kept it a secret, like he did with Deb

It is unclear at the time of this writing how much Doris Morgan will appear in Original Sin flashback scenes. The fact that she and Harry lost a child provides additional context surrounding Dexter's adoption. It is also not determined how close Doris and Dexter were during their teenage years. Odds are they weren't very attached. It would be shocking if Dexter: Original Sin revealed that Doris knew about Dexter's Dark Passenger and Harry's Code before her death in future episodes. Harry probably kept it a secret, like he did with Deb all those years.