Cally Lonegan is based on Whitey Bulger.
Actor Robert John Burke (Agent Ron Innes) goes on to play Internal Affairs Detective Lieutenant Ed Tucker in 29 episodes of Law & Order: Special Victims Unit (1999). Lieutenant Tucker also dates Mariska Hargitay's character Sergeant Olivia Benson for a time.
Kevin Elden has played five different roles over the course of the series:
- Episode 9.1 Cherished (1998) - Oscar Castellano.
- Episode 9.14 Sideshow (1999) - CSU Detective Kett.
- Episode 10.1 Gunshow (1999) - Dan Hayala.
- Episode 11.21 Brother's Keeper (2001) - Payton.
- Episode 14.8 Embedded (2003) - Bernie.