Diamonds for Breakfast (1968)

Swinging playboy Grand Duke Nicholas Goduno, a direct descendent of the Romanov family who were overthrown in the Russian Revolution of 1917, learns that his family's crown jewels will be exhibited at a London museum and plots to steal them. To this end, he gathers a crew of beautiful but dangerous women, led by Bridget Rafferty, to assist in his plot against Popov, the Soviet functionary in charge of the exhibit.