Plug That Leak! consists of a tall tank of water, with a sandy bottom, from which a stream of material resembling oil, jets upwards. On reaching the surface it forms a dense layer, which is continuously recovered along the back edge of the tank, and returned to a reservoir below.
The task of the game
is to stop the leak. For this there is a boat, which features a manoeuvrable derrick, controlled by the player.
Lying at the bottom of the tank there are a number of items, which can be picked up and otherwise manipulated using the grab at the end of the crane's cables.
The operator must attempt to place one or more of these objects into place to block the leak. Successful stemming of the flow releases a suitable reward that is stored in a separate chamber. This is a difficult task requiring great skill and patience because of the turbulence, and the fact that the crane's grab is being operated under water at the end of long cables
Upon timing out, the game resets itself by delivering a fresh mini explosion of oil mixed with a blast of air. This scatters the assembled objects over the bottom of the tank, and in a short space of time, the water clears enough to allow the game to resume on depositing more money.