A triangle is formed from matchsticks. A five-cent coin is placed inside. The whole thing is covered with a playing card. If this structure is taken apart again, the coin disappears without a trace!

So far so good... (... and perhaps already known).

But now the box is opened. In the middle of the sticks lies the missing fiver!

And everything can be examined immediately—matchbox, stick, coin. No trace of an "M..."!