Maddie, a local reporter investigating a series of killings targeting similar looking women is caught off guard when her younger sister Olivia, is attacked in her own home. Urging on the side of caution, Maddie suggests they take a self-defense course. When Olivia starts to fall for their instructor, Maddie becomes skeptical when he refuses to reveal anything about himself, and tries to intervene before the relationship turns into a deadly obsession.
Unfortunately the movie My Sister's Serial Killer Boyfriend is not yet available on HBO Max.
| Crew | Jasi Cotton Lanier | Stunt Coordinator |
| Directing | Danny J. Boyle | Director |
| Writing | Andrea Shawcross | Writer |
| Writing | Bryan Dick | Writer |
| Production | Ken Sanders | Producer |
| Production | Elle Sunkara | Co-Producer |
| Production | Elle Sunkara | Line Producer |
| Production | Joseph Wilka | Co-Producer |
| Production | Timothy O. Johnson | Executive Producer |
| Production | Sheri Reeves | Co-Executive Producer |
| Sound | Steve Gurevitch | Original Music Composer |
| Camera | Robert Vardaros | Director of Photography |
| Editing | Andrew Harwood | Editor |
| Production | Jeff Hardwick | Casting |
| Art | Jason Cronburg | Production Design |
| Art | Jeremiah Mann | Set Decoration |
| Costume & Make-Up | Taylor Jones | Costume Design |
| Costume & Make-Up | Melody Kelly | Hairstylist |
| Costume & Make-Up | Dana Kelly | Hair Department Head |
| Costume & Make-Up | Cheridan Smith | Makeup Artist |
| Costume & Make-Up | Haley Stefancis | Makeup Department Head |
