Basil Dearden directs Roger Moore, Olga Georges-Picot and Hildegard Neil in this London set doppelgänger mystery.

Whether you approach it as puzzle to solve or a camp time capsule back to the suits and home furnishings of middle class Britain of the Harold Wilson era, there’s much to enjoy here. Not least of which is our Rog’s performance – admirably straight, often convincingly desperate and open, with not a raised eyebrow in sight. Quite right too.

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