 Vernon Scripps and David are on their way in a tanker when they are forced off the road by an oncoming car. None of them get seriously hurt when the tanker overturns, but Vernon Scripps has a temporary loss of memory. Dr. Alway gets him admitted to his own hospital The Royal in Elsinby. The contents of the tanker ooze out on the ground and into a river and several people show signs of poisoning. Vernon Scripps is the only one, who knows what is in the tanker, and the hospital staff will not let anybody talk to him. Getting the tanker contents analyzed will take days and meanwhile nobody is allowed to use the tap water.