Thomas Jefferson Geronimo (Joe Don Baker) is a deputy sheriff working in a small town in South Texas. When two mafia hit men try to escape across the border to Mexico, Geronimo - with the skill of a quick-draw gunfighter - kills one and captures the other. When Geronimo tries to take his prisoner to Italy for extradition, they find themselves on an unplanned layover in Malta.
Geronimo's prisoner escapes, and the Texas lawman must battle the Mafia and local law enforcement to finish the job he started.
- Joe Don Baker as Thomas Jefferson Geronimo
- Rossano Brazzi as Don Lammana
- Venantino Venantini as Joseph Palermo
- Patrizia Pellegrino as Gina
- Greydon Clark (who co-stars as Geronimo's partner that is shot at the beginning by the film's main villain) had previously directed two other comedy movies with Baker (Wacko, Joysticks). Clark also directed Angels Revenge (with Jacqueline Cole and Jack Palance). Clark's other projects include the alien horror film Without Warning (again with Palance), Tom (again with Cole) and many other infamous exploitation films, some of which have been used by RiffTrax. In Final Justice, Clark also plays the DJ on the radio station overheard during the opening credits.
- In 2017, Final Justice became a RiffTrax presentation, with new jokes.