Madame Sin is a 1972 British thriller film directed by David Greene and starring Bette Davis, Robert Wagner, Denholm Elliott and Gordon Jackson.

[1][2] Ex-CIA agent Anthony Lawrence is abducted from London and brought to the Scottish Highlands on the orders of Madame Sin, an international criminal who runs her own organisation.

She uses this as leverage to get Lawrence to cooperate with her plan to steal a new Polaris nuclear submarine which is due to be tested in nearby waters and sell it to foreign radicals.

Barbara then appears alive and well and is held hostage while Lawrence returns Cavendish to the naval base to carry out the rest of the plan.

[6][5] Time Out London wrote "Lots of exotic sets and outlandish secret weapons, just a pity it's all rather old hat Bond stuff.