Clint Eastwood heads westward in 1969 musical Paint Your Wagon AKA Purty Harry.

In a possible attempt to rebottle the success of Oklahoma!, Lerner and Loewe’s (My Fair Lady) musical follows drunken prospector Ben Rumson (Lee Marvin) and his “Pardner” (Clint Eastwood characters aren’t allowed names) during the California Gold Rush. Setting up camp in a ramshackle mining town known as No Name City (“Population: Male”), the duo soon strike gold in the form of the beautiful Elizabeth (Jean Seberg) who’s just gotten out of a serious relationship with a Mormon (and his wife).

The only thing more surprising than the existence of a Clint Eastwood-starring musical is its quality, a rollicking minecart ride through the Old West that laments the loss of its freedom while poking fun at its practices. After a rocky start where Elizabeth is sold to the highest bidder, the story turns on a dime and has her marry both Marvin and Eastwood; a relationship-type seldom seen on screen (unless you know where to look).

This picture of old-school liberalism and anti-organised religion eventually collapses in an explosively entertaining climax, but not before giving Eastwood and Marvin a chance to show off their surprising (again) singing chops. Marvin is brilliant as Ben and did all the drinking for real like a true professional, adding strain to an already fraught production. Director Joshua Logan (Bus Stop) had the mining town constructed for real, which took 7 months to build and doubled the film’s budget; all gold and no rush.

While the songs are no match for Rodgers and Hammerstein, screenwriter Paddy Chayefsky (Network) sprinkles the 2.5-hour runtime with enough comedy gold dust to ensure Paint Your Wagon never drags.