Whether it be for good or ill, it is hard to deny that many of us have an appetite for spectacle. Our ancestors gathered to see gladiatorial battles, public executions, dramas acted on the stage, circuses, political rallies and ships launched to sea. The spectacular might not be to everyone’s taste but has enough appeal to make circus performance a viable trade over a long history with a business model based on ticket sales. Spectator sports exploit this same human curiosity: a desire to see something remarkable; to witness exceptional human feats, to have all one’s senses filled in an immersive and thrilling experience.