Mark Parsons was a Sergeant in the United States Marine Corps.
In addition to that, Parsons was also a contract killer who later died at the hands of another fellow contract killer, Tiffany Chase.
He also had an extensive collection of watches (presumably trophies from his victims).
During his career as a killer, he traveled to New York and later shot dead a real estate mogul named Sam Thoresen, making Thoresen's death look like the mogul had died in a home invasion.
Chase killed Parsons by breaking his neck before dumping his body in a bath full of kitty litter and she later fled the scene but despite her efforts, Parsons's body was later found by a housekeeper, prompting NCIS to be called in to investigate the circumstances surrounding Parsons's death.
- Five unnamed victims.
- Sam Thoresen- (shot dead).
- Nora Williams- (intended).