Uncle Maurice buys old broken animal cages and iron rods from dismantled animal cages amongst other scrap metal for resale. There appears to be a sudden and desperate demand for these broken down cages and iron rods. In the meantime The Trio Investigators are contacted by Alf Hitchcock on behalf of his friend Jim Newto who owns Royale Forest. Jim rents his forest with wild animals to film companies for movie makings. Jim wants the trio to investigate the reasons why his tame lion which he rents out to movie makers has suddenly become nervous. Read on and find out the strange connection between the sudden desperate demand for iron rods from broken down animal cages and the nervous lion. The story is a tangled web of intrigue, gripping suspense, mystery, tense drama and adventure.