A woman went over the railing at the Detroit Riverwalk about 8 p.m. Monday and into the Detroit River.

A man had a decision to make: let the woman drown or save her -- a choice that could have cost him his own life. The man was working on the Detroit Princess boat when he saw the woman in trouble. He grabbed a life preserver and dived in.

The hero saved her from almost certain death.

No one really knows what they would do if they saw someone in a life-or-death situation. This man didn't either.

Perhaps he even surprised himself.

The man works for the Marine Division on the Detroit Princess boat. There were no guests on the boat at the time.

Man who saved woman from river