Electra Glide in Blue (1973)
When pint-sized motorcycle cop John Wintergreen believes a suicide is a murder, he gets his wish and is transferred to the homicide division. Unfortunately, the satisfaction from his promotion is short-lived and so begins a slow descent to a famously tragic conclusion.
Such was his faith in cinematographer Conrad Hall, director James William only paid himself a salary of $1 to free up the budget needed. Now that's devotion.