I'd make a tressle type table with the top of the table be plywood sawn in half in a jagged line.  Under the table I'd have two brackets (sets of brackets that during most of the play have a pipe through them to join the table securely.  During the part where the table breaks, I'd have rigged by cables to draw the two pipes simultaneously back past the "break line".  The table falls under it's own weight.  Then when the next performance comes simply reinsert the pipes.

 

If the brackets don't allow the pipes to move smoothly, replace them with a slightly larger pipe (sawn in two, one piece mounted on each side of the jagged break) that you attach to the table underneath and grease to allow smooth movement.  The small pipe acts like the bolt in an old fashion door slide bolt lock.  The larger pipe or brackets act as the slide for the bolt.

 

Good luck!