Two magicians, twins and a duplicating machine
Alfred Borden performs 'The New Transported Man' by secretly being identical twins who share a single name, career, wife and mistress, alternating one public life. His rival Rupert Angier buys a machine from Nikola Tesla that truly transports a man, but each use leaves a copy behind at the starting point. Angier performs it nightly and hides the resulting bodies in the family crypt, so a century later his descendants inherit the question of which Angier survived.
