This 35mm screening is part of the Warren Beatty season at the Prince Charles Cinema. You can find all the details here.
Time Out review:
Made with all the awareness of hindsight, Shampoo offers a sharp sexual satire and a mature statement on both America and Hollywood in 1968, The Graduate as it should have been, perhaps. Everyone is shown to act out of the same fatal expediency, as the country elects Nixon for President while Warren Beatty's chic Hollywood hairdresser tries to sort out an increasingly dishevelled sex life, a campaign against the Establishment via its wives and mistresses that's subversive only by default. Ostensibly a farce about fucking for fun and its repercussions, but the laughs are tempered by bleakness and the film ends up saddened by its characters' waywardness.
Here (and above) is the trailer.