While Johnny Ashley (Anthony Steffen) is away from home, his ranch is attacked by the ruthless Mexican bandit El Chacal (Fernando Sancho) who murders his wife and abducts his five year old son Jerry. Thereafter Johnny rides the range, obsessively hunting down every man in El Chacal's gang in the hope they will lead the way to his mortal enemy and missing boy. Fifteen years later Jerry (Roberto Miali, billed as Jerry Wilson) grows into a sadistic gunslinger in black, terrorizing the territory as El Chacal's trusted right hand. The pair plot to rob town bank. Meanwhile Johnny arrives in town and fate sets him on a collision course with Jerry with neither aware they are father and son.
Revenge tends to be the dominant theme in Italian westerns. Despite their pop cultural status as the gritty, uncompromised alternative to Hollywood the plots were less diverse than in classic horse operas. To its credit 7 Dollars on the Red attempts to fashion a more ambitious variation on the standard revenge yarn, part-influenced by Greek tragedy. Book-ended by contrasting scenes of mass murder (the opening massacre somewhat undercut by the poor performance of the actress playing Johnny's wife), the film starts with a solid theme. Early on a friend warns Johnny revenge will do little but transform him into the kind of remorseless killing machine he purports to hate. As things turn out however it is his son Jerry that develops into a heartless bastard under the influence of the hateful El Chacal, murdering men for kicks and callously manipulating then brutalizing women. This proves the first of several left-field turns throughout the film that tread a fine line between intriguingly unexpected and plain inconsistent. While the Oedipal aspect of the drama evokes the brooding psychological westerns of Anthony Mann, for the most 7 Dollars on the Red wastes a lot of time meandering from one pointless violent encounter to another without developing its themes.
The re-shoots may well have been necessary to get the film back on track given Cardone pads the plot with long, tedious sequences where Johnny gets brutally beaten again and again. Along with a tendency to wallow in repetitive sadism the film deviates from its core theme with a tragic romantic subplot. Sweet-natured showgirl Sybil (Elisa Monté) rashly ignores the warnings of the more experienced Emily (Loredana Nusciak) and takes up with the no-good Jerry whose attitude towards women is shaped by the comic book misogyny of El Chacal ("Let me warn you about women-folk. They're worse than rattlesnakes! Give them a chance and they'll ruin your life!"). Undercutting the otherwise somber tone, spaghetti western staple Fernando Sancho delivers another greasy slice of ham as he rants and raves, slapping women about with abandon. However Anthony Steffen carries the film with one of his stronger turns as the embittered hero whose actions are weighed down by grief, rage and in the closing scenes remorse. The climax which pits bandits against the entire town is a memorable set-piece that stands out from the bulk of the film, possibly inspired by the real life ambush that put an end to the Dalton gang.