It's not just martini's shaken but not stirred that are quintessentially James Bond. With each of the 24 Bond films spanning 50 years comes a theme song that sets the scene for the film and the year it was made. Two Stanford University professors have analysed the Bond themes, from Shirley Bassey's classic 'Goldfinger' in 1964 to the new Sam Smith song for Spectre. Their book, The James Bond Songs: Pop Anthems Of Late Capitalism argues why theme songs don't just set the mood for a Bond film but also tell a story about the evolution of pop music.