The film's MVPs are Bryan Cranston's dedicated performance as the title character, and, appropriately, John McNamara's jocular screenplay, with a terrific ensemble of supporters also along for the ride back to Hollywood's notorious past

Bryan Cranston creates a potent sense of Trumbo as a reasonable man, full of charm, eloquence and principle and he is surrounded by a string of performances to savour.

What makes the movie work are the lively performances, both from the supporting cast and from Cranston, who sheds the mimicry and pontificating of earlier scenes to turn Trumbo into a wry, self-deprecating and somewhat cheeky older man, even if he continued to stand up for what was right.

The drama is stuck with that ethical rigor, and we are left with a near-heretical irony: thanks to this admiring tribute, our hero gets top billing at last, but was he not more beguiling, somehow, as a legendary figure in the shadows?

[Jay Roach] wants the film to be fun, while the story is serious. It’s a good idea and an admirable intention. But it does suffer the odd wobble.