There was a show on DC channel 20 Monday night called “The Magician’s Code Revealed” or something like that, where they showed how some magic tricks are done, like the floating seance table, and escape from cage from behind a backlit screen.
But I had to turn the show off before they showed the end of the “imprisoned in ice” endurance bit. So what did they show after he had been in there for a few days?
If it’s the same one I saw a while back, basically the magician had a double who slipped in through a hidden trap door while the assistants were spraying down the ice with “white misty whatever”, which concealed the exchange. Beneath the trap door was a tiny room, with all the comforts of home, enabling the magician to chill out (heh) for hours at a stretch. He and his double would swap back and forth as required. Not much to it, really.