I found out more about the movie. Made right before Steve McQueen did Great Escape. Two Naval officers were on leave and ran into civilian at the Lido casino who said that odds could be computed if they knew the past series of positions of the roulette ball. They recorded the positions and used a signal lamp to send them to their ship, officer on ship entered them into computer and relayed via signal lamp back the predicted next winning position. I think they always bet on the top 3 predicted positions. They were staying in a suite at the hotel and ran into a cute young women who turned out to be the admiral's daughter. The admiral was staying at the suite downstairs and noticed the flashing signal lamp and thought there were spies around. Nobody could decode the Morse code signals of the roulette positions. Finally all were found out and confessed to the "gambling". Mike