Australian-born actor Rod Taylor starred as “salvage consultant”-cum-detective Travis McGee in the 1970 theatrical release Darker than Amber, adapted from John D. MacDonald’s 1966 novel of the same name.
This fight scene late in the picture between Taylor and the villainous Terry (played by William Smith) is notorious for having become much more violent than anyone planned. According
to Wikipedia, “With the cameras rolling one actor accidentally struck the
other (no one has ever revealed who struck the first real blow), the second
threw a retaliatory punch, and a staged fight scene became a real fight, with
real wounds, real lost teeth, and real blood all over their clothing.”