Glass is pure. Glass is transparent. Glass is sharp. Gunter Glass, ex-milkman and aspiring window-cleaner, is certainly pure. And he's pretty transparent. But the jury's still out on how sharp he is. What naive young Gunter does have is a head for heights and, ever since he visited a glassblower's workshop as a child, an unusual fixation with glass. When a minor adventure up the spire of Salisbury Cathedral makes Gunter a local celebrity, John Blades - window-cleaner to the stars - comes calling. He wants Gunter to join him in London to clean Europe's tallest skyscraper, the newly constructed Shard in London Bridge. With his mother recently passed away, his dad retired and no money to pay off the mortgage, Gunter takes Blades up on his offer and soon finds himself, for the first time, among the bright lights of London. He has his first experience of romantic love with short-range psychic Lieve Toureau, tries not to encourage Blades' frequent racist outbursts, and cohabits a Hackney 'bachelor-pad' with a reclusive landlord who has spent decades writing a never-ending book in his cork-lined bedroom. But above all, Gunter spends his time trying to figure out how to be good and follow his dear departed mother's advice as best he can. Will Gunter find his way along the straight and narrow? Or will his innocence put him on collision course with the frequently baffling modern world?