This was the film that was supposed to make PC a proper bona-fide film star. All the elements were in place - a script from John Cleese and Graham Chapman, a stellar cast of British acting talent, major studio support from Warners, and even David Frost as Exec Producer.
Cook himself looks great - really rather handsome, and although his acting style was on the arch side, he got away with with because the character he was playing was such a smoke-and-mirrors PR fraud (Alastair Campbell must've seen it...).
However, it all went wrong. It was such an audacious, accurate satire of the machinations behind a political party scheming its way to power, that it was deemed politically too sensitive to release in the midst of the 1970 general election. It eventually got a modest release, but the moment had passed, and so had Cook's stab at movie fame. Dudley did slightly better a few years later...
That said, it's great. Chillingly predicting the annexing of party politics by spin, image and grasping PR chancers, "Rimmer" is a joy, and even an education.