Dexter: Original Sin: Where to Watch, Cast & Everything We Know So Far

When it originally premiered, there was nothing else like Dexter on TV.

Our volatile relationships with antiheroes were suddenly under a microscope, as Dexter analyzed blood spatter at crime scenes while setting up his next victim -- those he believed weren't meted the appropriate dose of justice.

Dexter Morgan was a serial killer, Robin Hood, doing the work law enforcement failed to do.

Although Dexter finished its award-winning eight-season run in 2013, the man, the myth, and the legend live on.

He was first revisited with a Showtime original series, Dexter: New Blood, in 2021. If the original series ending didn't satisfy, Dexter: New Blood proved equally as divisive. Yet, still, we tune in.

Shortly after New Blood, it was announced that a spinoff focusing on his son, Jack, would take flight. We haven't heard much in that regard since, as the focus has shifted to a prequel, which will show how Dexter became the man we knew him to be.

Who is Dexter Morgan?

Readers were first introduced to Dexter Morgan in a series of books by Jeff Lindsay and the television viewing public in the Showtime series Dexter. The series took Lindsay's story in a different direction, and what follows comes from the series.

Dexter was a forensic scientist in blood splatter working in the Miami Metro Police Department.

His sister, Debra, was an officer of the law and detective in the same department.

Dexter was adopted by Harry Morgan, and his parenting style was a bit peculiar, leading his son down a path with his "dark passenger," a psychological byproduct with which he became judge, jury, and executioner for criminals he didn't believe would be dealt justice.

He was a serial killer with a conscience, although that nagging moral code was less reliable as time went on.

Dexter was capable of emotion to some degree, as could be witnessed by what he shared with Debra and how he counted on her.

His marriage to Rita Bennett was as happy as the marriage of a serial killer hiding behind a purpose could be and produced a child, Harrison. As his life began to crumble and his sister Debra was killed, Dexter lost control of his Dark Passenger.

To escape the madness his life became, Dexter entrusted a close friend with his son and faked his death.

In the series Dexter: New Blood, it was revealed that Dexter was alive and living as Jim Lindsay (surely a throwback to his creator), and Harrison tracked him down.

Their tumultuous relationship suggests Harrison may be harboring his own Dark Passenger, and rather than continue to guide his son as his father did him, Dexter asks Harrison to kill him for his failure as a father and to break their bond before it does more damage.

What is Dexter: Original Sin About?

The new series will begin 15 years prior to our introduction to Dexter in the original series.

This new ten-episode thriller will chronicle America’s favorite serial killer...in training.

Set in 1991 Miami, Original Sin follows Dexter as he transitions from student to avenging serial killer.

When his bloodthirsty urges can’t be ignored any longer, Dexter must learn to channel his inner darkness.

With the guidance of his father, Harry, he adopts a Code designed to help him find and kill people who deserve to be eliminated from society without getting on law enforcement’s radar.

This is a particular challenge for young Dexter as he begins a forensics internship at the Miami Metro Police Department.

Who Stars in Dexter: Original Sin?

Patrick Gibson stars as Dexter Morgan, following in the footsteps of Michael C. Hall, who created the role.

You may know Gibson from The OA, where he starred as Steven Winchell, or Shadow and Bone, where he played Nikolai Lantsov.

Christian Slater stars as Harry Morgan, following in the footsteps of James Remar, who created the role.

Slater has been a part of popular culture for decades since he broke out in the cult film Heathers. He followed that with a memorable performance in True Romance and later earned raves in the critically darling Mr. Robot TV series.

Patrick Dempsy has also joined the cast as Aaron Spencer, the Captain of the Miami Metro Homicide Department who has a decades-long relationship with Harry.

Sarah Michelle Gellar is the latest high-profile actor to join the series. She will play the special guest-starring role of Tanya Martin, the CSI Chief at Miami Metro. She's also Dexter's new boss.

Molly Brown plays Debra Morgan, following in the footsteps of Jennifer Carpenter, who created the role. Brown, who currently appears on the Paramount+ series Evil, has also starred in the feature film Senior Year.

Emmy nominee Clyde Phillips (Dexter, Nurse Jackie) will return as showrunner and executive producer.

Is Dexter: Original Sin a Limited Series?

We have no word yet about the length of this series.

But as networks lean into IP and the damage done to Dexter's psyche that turned him into a bit of a psycho being extensive under Harry's tutelage, I expect this to last more than one season -- assuming it does well for the network.

How Many Episodes Will Be in Dexter: Original Sin?

This new series has an order of ten episodes at present.

While it's not being called a limited series, again, don't expect it to continue unless it does well for the network.

Dexter: New Blood did well but once again disappointed fans with its ending, so whether the fans are willing to return for another round is up for debate.

However, taking the prequel route has a set ending, and it's harder to disappoint sharing backstory than it is a new future.

When Does Dexter: Original Sin Premiere?

It's too early for a premier date right now, but with casting currently underway, I'd wager we'll see it sometime in 2025.

Where Can I Watch Dexter: Original Sin?

While the name change is still rather confusing, you can watch Original Sin on Paramount+ with Showtime, formerly Showtime, which is also now housed on Paramount+ with the "with Showtime" addon.

Hey, we didn't say it would be easy.

Is There a Trailer for Dexter: Original Sin?

There is no trailer at this time, as casting is still underway. However, when we have one, we'll be sure to include it!

Carissa Pavlica is the managing editor and a staff writer and critic for TV Fanatic. She's a member of the Critic's Choice Association, enjoys mentoring writers, conversing with cats, and passionately discussing the nuances of television and film with anyone who will listen. Follow her on X and email her here at TV Fanatic.

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