Go off the rails

A train going off the rails
A train that has gone off the rails.

If someone loses complete control of their behavior or emotions, then you can say that they have gone off the rails. We use the expression go off the rails to refer to someone who has started to behave in a strange or abnormal way. In many cases, their actions are considered to be inappropriate or unacceptable compared to their usual standards. As a result, they are likely to cause damage either to themselves or others. We can also use this expression to refer to non-living things, like machines, projects, or even political campaigns, for example. When something goes off the rails, it functions differently than normal.

This phrase gets its meaning from trains. If a train goes off the rails, then it falls off its intended path, which could cause a crash or other damage. For this reason, we generally use this expression to refer to a negative change in condition. For example:

  • My son has gone completely off the rails these days. He has been misbehaving at home and his teacher called me to say that he has also been skipping class. I need to have a serious talk with him.
  • A lot of young adults go off the rails when they move out for the first time. I think their newfound freedom makes them behave more liberally than when they lived at home with their parents.

A. Long time no see, Larissa! How’s your project going?
B. To be honest, not that well. It kind of went off the rails after our manager got transferred to another department. Without her, we’ve lost a bit of direction and organization.

Did you know? This idiom has been around since the mid-1800s. We usually pair the phrase "off the rails" with the verb "go"; however, it can also be paired with the verb "be."