The series consists of 18 episodes, each of which covers a particular set of machines. The series uses animation to help explain various aspect of how the subject devices function. The animation for the series was done by Hunkin himself in a uniquely recognisable format.

How does a car work? And how about an internal combustion engine, a quartz watch, a telephone, a radio set, and a video recorder? The Secret Life of Machines (Series 2), consisting of the second six episodes of the series, investigates devices used outside the home.