Some people can do it and some can't – sit down at the keyboard and simply make music up on the spur of the moment. The piano can be the perfect instrument for jazz improvising, capable of a vast range of sounds from the percussive to the lyrical. But there are many ways to improvise – classically trained players may choose to follow clear structures in improvising, for instance in the cadenza of a concerto; and jazz musicians will often have at least a fixed chord sequence from which to elaborate; whereas a silent film accompanist often improvises spontaneously to a film which may last for an hour or more, having never seen it before sitting down to perform to an audience of cinema-goers. And in the genre known as Free Improvisation, the pianist tries to avoid all pre-thought or pre-arranged structures, and be completely open to the ideas of the moment when hammer strikes string. Featuring Gwilym Simcock, Stephen Horne, Harry the Piano and Ivan Ilic.