Plot: The next step of Jonathan Foyle's journey takes him to the Glasgow School of Art, built from 1897 by young artist Charles Rennie Macintosh, it's one of Britain's most controversial, challenging and celebrated buildings. With unprecedented access Jonathan, aided by top climber Lucy Creamer, scales the school to reveal the myriad of influences, from medieval castles to Japanese heraldry, that Macintosh used to create his modernist masterpiece