What's Going on in Beely Circus? [Was ist los im Zirkus Beely?]

Harry Piel plays Harry Peel who receives an urgent telephone call from a friend who has returned from South America recently. The call is being made from the circus "Beely" and our hero arrives there too late to prevent the murder of his friend. Now Harry must find his friend's killer and go on a strange mission involving a hidden document.