I was in a truck which was NOT in gear when the driver got out. The trouble is that I was in the back getting out my gear when it started rolling toward the lake. I jumped out of the bed, ran around to the passenger side as it was closest and tried to unlock the door... only to remember the key only worked on the driver's door. I ran around the back of the truck, got it unlocked and jumped in... just as the truck hit a high spot and came to a stop.