A rollercoaster of a show as Tom experiences how music gets our hearts racing. How do composers from Bach to Jarvis Cocker manipulate speed in music? How can a slow movement by Sibelius be 'faster' than 'speedcore' dance music? Tom takes us inside the mechanics of speed, and discovers that Sibelius controls our heart rate in symphonic music in the same way that a DJ in Ibiza does as their set unfolds. Just to put his theories to the test, Tom rides a roller coaster with the composer Anna Meredith who explains how those mighty rides do much the same thing as she does when writing the music designed to get our pulse rate up.