Jack Beauregard is a tired, aging legendary gunslinger who just wants to retire in peace in Europe to get away from young gunmen constantly trying to test themselves against the master. The film opens with three rascals ambushing Beauregard in a barbershop. After Beauregard has dispatched them, the barber's son asks his father if there is anyone in the world faster than Beauregard, to what the barber replies "Faster than him? Nobody!"
'Nobody' idolizes Beauregard and wants to see him die in a blaze of glory going against the infamous Wild Bunch singlehanded. The Wild Bunch are a gang of bandits who launder their loot of stolen gold via a fake goldmine. The owner sends them after Beauregard because the latter's now-dead brother was in on the deal.
Nobody dogs Beauregard through the west, encountering many who wish him dead, and pesters him to let him stage his grand finale. Eventually, the grand shoot-out does take place by a railway line. Nobody arranges for Beauregard to shoot at the Wild Bunch's mirrored-concho-decorated saddles which, he's discovered, contain sticks of dynamite, thus letting a few good shots eliminate many of the men. To escape, the two board a train that Nobody has stolen.
Finally, Nobody fakes a very public showdown with Beauregard, "killing" him and allowing him to slip away quietly. A street sign, marking where the gunfight took place, says "Nobody Was Faster On The Draw". Beauregard boards a boat for Europe and a quiet retirement, while Nobody takes up his own life of adventure.