Two dumbwaiters, stacked one on top of the other, allow Problem Sleuth and Ace Dick swap small items back and forth without actually visiting the other's office. The dumbwaiter shaft ascends all the way up to just outside Mobster Kingpin's office, covered by the dreaded Bowen Stilson Dogg. This shaft, the bust, and presumably both dumbwaiters were very thoroughly demolished in a Hot Sauce-related explosion.