To be in hot water is to be in serious trouble. Land in hot water, in hot water with the boss, get into hot water.
It is milder than being in real danger and usually means official displeasure. It goes with land, get and be, and the trouble is nearly always with somebody in authority.
1phrasein hot waterIn serious trouble.
“The email put him in hot water with the whole board.”
in hot water is a phrase.
Practised in Idioms