In films generally, as in life, jewellery has a wide range of possible associations. These may be romantic: in two early Garbo films – THE TEMPTRESS (Fred Niblo, 1926) and FLESH AND THE DEVIL (Clarence Brown, 1926) – she and the hero signal their love by exchanging rings. But, as a gift from a man to a woman, jewellery may equally connote the man's sense of his own status and wealth, as in the familiar situation of a husband wanting his wife to wear the expensive jewellery he has bought her. Such jewellery may have little sentimental value: RANDOM HARVEST (Mervyn LeRoy, 1942) nicely contrasts the expensive emerald pendant the hero gives the heroine when he is a famous politician with the much more highly valued cheap necklace he gave her during his amnesiac period, when he genuinely loved her. Similarly, both the engagement and wedding rings, with their familiar connotations, have been used in films to signal such matters as the owner's feelings about the relationship symbolised by the ring, or a woman's sacrifice in giving it up, as in GONE WITH THE WIND (Victor Fleming, 1939).

From early in his career, Hitchcock has used jewellery in his films, but almost invariably with illicit or sinister overtones. These may be summarised under a series of subheadings, listed here in approximate order of increasing importance.

Greed

In DOWNHILL, Julia's fleecing of the naïve Roddy is symbolised by the box of jewels she has – among other possessions – converted his inheritance into; her lover Archie advises her to put the jewels in the bank to prevent Roddy getting at them. IN FAMILY PLOT, Adamson, a jeweller and kidnapper, insists on each of his ransom demands being met by payment in a single, massive diamond. Greed, however, is not really a Hitchcock preoccupation. Support for his indifference may be found in the cavalier treatment of the diamond necklace in NUMBER SEVENTEEN. As Charles Barr argues, the necklace functions in the film exactly like the (later very familiar) MacGuffin (Barr 1999: 125) (➢ THE MACGUFFIN).