The acting is absolutely tremendous.
Langella doesn't look like Nixon at all, but this is far more than a work of mimicry. Any half-decent lookalike can purse lips into that unforgettable scowl and raise a couple of V-shaped hands, and even Oliver Platt, who plays one of Frost's assistants, does a pretty spot-on Nixon impression during one of the film's lighter bits -- but what Langella does is create the world leader from the ground up, to create a fully fleshed out character it is impossible to dismiss as just a scamster. It is a bravura performance, and deserves every bit of applause.
Sheen is equally exciting, even though Nixon is clearly the author-backed character. Sheen takes his character on a wild ride, traversing a breathtaking arc as he goes from cocky and self-assured to completely out of his depth. He is a perfect foil to Langella, and the actors play off each other beautifully.
Their fencing -- as Nixon backhandedly, confoundedly (heck, even adorably) complements Frost's shoes; or as Frost takes over a date for his first Nixon visit - is artful beyond what is seen in cinema today, evocative far more of the 70s.
The entire cast is great, especially Toby Jones as Swifty Lazar. Platt is fun, while Rockwell overplays earnestness just a tad, but is believable nonetheless. Matthew Macfayden, glimpsed last in the hilarious Death At A Funeral, is perfect as Frost's producer John Birt, and the lovely Rebecca Hall is fast becoming an actress to follow.
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