To go off the rails means that something has gone badly wrong or out of control. This idiom is used when a plan, situation, or a person's behavior stops following the expected path.
The expression comes from railway accidents. If a train's wheels leave the metal rails that guide it, the train can no longer move safely along the track and the journey quickly becomes dangerous to anyone on or near the train.
The expression comes from railway accidents. If a train's wheels leave the metal rails that guide it, the train can no longer move safely along the track and the journey quickly becomes dangerous to anyone on or near the train.
The meeting went off the rails once everyone started arguing.