Marcus Giamatti (1961 - )
- Hamlet (2000)
- The X-Files: Jump the Shark (2002) [John Gillnitz]: Dies of a genetically engineered virus emitted from the shark organ in his body (as part of a terrorism plot), after Tom Braidwood, Dean Haglund, and Bruce Harwood sacrifice themselves by trapping themselves with Marcus.
- NCIS: Los Angeles: Wanted (2013) [Michael Snyder]: Shot repeatedly in the chest in a shoot-out with Timothy V. Murphy.
- Son of A. Bartlett Giamatti (National League Baseball commissioner)
- Brother of Paul Giamatti