bottom drops out
A phrase used to describe something that ends or goes awry abruptly. Work quickly to close that deal—the boss will be furious if the bottom drops out at the last minute.
bottom drops out, the
Also, the bottom falls out. A collapse occurs, as in The bottom dropped out of the steel market, or When they lost the game, the bottom fell out of their hopes to make the playoffs. This term alludes to collapsing deeper than the very lowest point, or bottom. [First half of 1600s]