Emma Thompson wears an unidentified watch

Karen's storyline is the quiet heartbreak in Love Actually. She finds a gold necklace in her husband Harry's coat, assumes it is her Christmas present, and unwraps a Joni Mitchell CD instead; the necklace was meant for someone else. Emma Thompson plays the moment she breaks down alone in the bedroom and then steadies herself for the children, one of the film's most-discussed scenes, and it is exactly there, with both hands pressed to her face, that the watch comes into view.

On Karen's left wrist sits a small elongated rectangular gold dress watch on a black leather strap, the curvex case and stepped lugs of a vintage American style from the 1940s or 1950s. The silvery dial carries applied numerals and a small seconds register low on its face, the kind of detail that reads as quietly tasteful rather than flashy, in keeping with Karen as the grounded wife. No maker's name is readable on the dial, and no reliable source has ever identified it. The shape is consistent with several houses of that era, Hamilton, Gruen and Bulova among them, so it stays an unidentified period dress watch rather than a named reference.

Richard Curtis's Love Actually (2003) braids ten London love stories together at Christmas, and Karen's is the one that does not resolve happily. The most-screenshotted wrist in Christmas-movie history wears a watch that has kept its own secret.