A new serial killer in Miami was dubbed "The Brain Surgeon" because he would saw into his victims' craniums and remove a portion of their brains. There were only two known victims before the killer's identity was uncovered.
Lyle Sussman was the initial and primary suspect in this investigation. The police were unaware that the true killer had used Sussman as a patsy and then murdered him himself, staging Sussman's death as a suicide to stop further investigation.
When Sussman's body was found, the police believed that Sussman was The Brain Surgeon and had committed suicide out of remorse. The case was then closed.
Meanwhile, the true "Brain Surgeon" still lived on and continued to kill, although these victims were not left in public areas. After he killed Cassie Jollenston, the police brought in Oliver Saxon (the true "Brain Surgeon") to be questioned as a potential suspect. However, they let him loose after falling for his lies. Eventually, Saxon killed his own mother, Evelyn Vogel, but her murder was not initially linked to the Brain Surgeon because he hadn't cut into her skull.
Later, Dexter enabled the footage of Saxon killing his victims to be broadcast on the news. His face was exposed and it proved that he was the actual Brain Surgeon. Saxon was arrested when he tried to kill Debra in the hospital.
The investigation ended when Dexter stabbed a pen into Saxon's neck at the jail, killing him. Dexter convinced Miami Metro that it was an act of self-defense by the security footage that showed Saxon attempting to kill him first.
- Richard Vogel Jr. - Drowned in pool
- Seven children in psychiatric hospital - Burned alive
- Unidentified girlfriends - Mentioned by Saxon to Dexter while on kill table
- Robert Bailey - Shot; skull sawed into postmortem
- Leonard Welks - Smothered; skull sawed into postmortem
- Lyle Sussman - Forced by Saxon to kill Welks, then shot in head by Saxon; falsely suspected as The Brain Surgeon
- Cassie Jollenston - Bludgeoned; skull not sawed into
- Zach Hamilton - Skull sawed into was still alive
- Evelyn Vogel - Throat slashed; skull not sawed into
- Max Clayton - Stabbed by Saxon after Clayton released him
- Debra Morgan - Shot by Saxon, had a stroke after surgery. Dexter shut off her life support and buried her at sea.
- Evelyn Vogel's House
- Lagoon Park
- Lyle Sussman's Hunting Cabin
- Miami Central Hospital
- Oliver Saxon's Apartment
- Rendall Psychiatric Hospital
- Skate Park
- The Treatment Room