With Go West (1940), the studio at least had the sense to allow the Marxes to test their material out on the road again. Unfortunately, the final results hardly seemed to justify the effort. Go West remains one of the dullest and uninspired films the team appeared in. Frustratingly, it actually opens with a very solid and funny scene, of the kind in which Chico and Harpo manage to pull one over on Groucho (in this case, while waiting at a train station to make the journey west). If the rest of the picture had managed to sustain the level of wit present in its opening scene, it might very well have turned out to be a perfectly enjoyable comedy. Instead, Groucho (in particular) gets mired down in painful one-liners that turn his normally fearless and cavalier screen character into a coward.
The unfamiliar setting of the old West no doubt works against the film as well, since the Marx Bros. were always more at home in contemporary surroundings, where they could wreak havoc on the established order of society. The writers fail to get any real mileage out of the Western genre as a subject for parody, instead simply dropping Groucho, Harpo and Chico into a routine Western backdrop without really making them integral to it. Add to this the fact that far funnier Western satires had already appeared – most notably Laurel and Hardy’s Way Out West (1937) – and Go West seems even more tired and ineffective in comparison. Throughout the 1940s and 50s, nearly every major comedian appeared in a Western parody at some point, though perhaps only Bob Hope’s Paleface films approached a level of real brilliance.
The generally humorless supporting cast doesn’t help matters any, either. Robert Barrat is hardly the comic foil that Sig Rumann was for the Marx Bros. in their first two MGM films. Walter Woolf King, who had appeared as a sufficiently unlikable heavy in A Night at the Opera is wasted here. And the romantic couple is bland and colorless to the point of being almost totally forgettable, making it even harder than usual to get invested in the film’s subplot (though leading man John Carroll is granted a nice tune, “Riding the Range”, which allows for a fun moment when Groucho and Chico join in).
As a result of its lackluster plot and performances, Go West plods through its 80 minute running time before arriving at its climax, involving a fast-action chase on a locomotive. Like the finale of Laurel and Hardy’s County Hospital and W.C. Fields’ Man on the Flying Trapeze, what makes this scene work so well is the obvious use of special effects and sped-up action, combined with casual cutaways to Groucho’s throwaway one-liners. It's not a bad comedy scene, though it perhaps seems better coming after so much lackluster material during the preceding 80 minutes.
Ultimately, Go West suffers from all the constrictions and restrictions of studio-era production, and is characteristic of the kinds of challenges presented by trying to produce a free-wheeling comedy within the confines of MGM’s factory system.