The Magic Christian

The Magic Christian, starring Ringo Starr and Peter Sellers, was the reason The Beatles were up against a deadline to record Let it Be. But it was also an actual film that you can watch and everything. How did Ringo get on in his first starring role without the others? Is its anti-capitalist theme expressed with any purpose? And why is Yul Brynner in it singing a Noel Coward song to Roman Polanski? (Spoiler: we can't answer this one.)