An even more extreme example was his notorious "sick bag" prank. This involved carrying on to an aircraft a tin of Heinz Russian Salad, which he would then surreptitiously empty into an air-sickness bag. At the appropriate point in the flight, he would pretend to vomit loudly and violently into the bag. Then, to the horror of passengers and crew, he would proceed to eat the contents. One April Fools' Day Humphries placed a roast dinner and glass of champagne in an inner-city rubbish bin. Later in the morning, when there were many businesspeople queuing at a nearby building, Humphries approached the group as a dirty, dishevelled man. He walked to the bin, opened the lid and proceeded to lift the roast and glass of champagne and drink from the glass. Much to the amazement of those watching, he found a suitable seating area and began to eat the meal. Such stunts were the early manifestations of a lifelong interest in the bizarre, discomforting, and subversive.