Here is a different science "surprise."

Something like 55 years ago, I was taken to Battersea funfair and one of the exhibits was "The Invisible Man." This consisted of a large glass box like a shower enclousure and around the vertical edges were lights, perhaps fluorescent tubes. Members of the audience went into this - I had a go myself - and as the showman turned a dial the person faded from view and 'turned invisible.' fFrom inside thre was no visible change to the audience. From neither inside nor outside was there any visible change in the brightness of the lights or anything like that. There was not the space - nor the necessary cooperation - for it to be based on "Pepper's Ghost" being over 55 years ago it must have relied on fundamental physics, not some hi-tech approach.

I wonder if somehow it relied on total internal reflection, but to this day I haven't decided precisely how it was done.