At lunchtime on May 15, 2001, CSX Locomotive No. 8888 eased down tracks in a rail yard outside Toledo, Ohio. The engine known as "Crazy Eights" picked up speed as it pulled 47 freight cars, two of them loaded with toxic chemicals, south toward Columbus.

Only no one was on board.

Jon Hosfeld, a native of Mechanicsburg, Pa., was in the rail yard eating his lunch.

He wasn't supposed to be there that day. Hosfeld, 52, ran a CSX yard 67 miles south in Kenton; he'd come north to deposit a carload of children and Ohio's lieutenant governor in Toledo for a program aimed at raising awareness about the dangers of rail crossings.

Over the radio from the tower came the foreman's voice: "I think we've got a problem."

It was a railroad worker's worst nightmare: a runaway train.

Hosfeld dropped his lunch. He and a coworker jumped into a silver Dodge Dakota pickup and took off.

If this scenario sounds familiar, maybe you've seen the trailers for Unstoppable, the thriller starring Denzel Washington that opens at theaters Friday. It's about an out-of-control train and the heroic effort to stop it before it caused widespread disaster.

That's Hosfeld's story.

Now he's 62, retired, and living in Marysville, Pa., near the rail yards where he and his father once worked.

"I've got to stop this train," he remembers thinking. "I've got to solve this problem."

A senior engineer that overcast spring day in the Stanley Yard, just south of Toledo, was moving cars around in the typical choreography of freight yards.

He was preparing to make a routine repair - to climb out of his slowly moving locomotive and fix a track switch. For reasons still unknown, he applied the throttle instead of a brake system.

Panicked, the engineer tried to jump back on the train. But he lost his footing on rain-slicked steps and was dragged 80 feet before he let go.

Meanwhile, Hosfeld, a veteran CSX trainmaster, saw what was going on. He says he remembers thinking: Let's see if we can catch it.

Off he went, he and his colleague Mike Smith, barreling down Interstate 75 in the silver Dodge Dakota, reaching speeds of almost 100 m.p.h. in a race to find the train. State police began clearing the rail crossings.

Hosfeld and Smith rushed to a crossing and peered down the tracks. No train. They didn't know if it was behind them or ahead.

They pressed on, finally catching sight of the train at a town called Cygnet. It was moving at speeds of more than 40 m.p.h.

"I could see the vapors," Hosfeld recalled this week in an interview. That telltale sign made his heart sink: "I knew the throttle was wide open."

His first thought was to derail the train.

Just north of the college town of Bowling Green, the railroad workers tried to do just that - they laid down a steel wedge designed to derail a locomotive in just such an emergency.

The Crazy Eights blew right through it at 50 miles per hour.

The train was sailing through dozens of grade crossings, moving too fast to trip the gates. It motored past factories, through cornfields and sugar-beet farms and the bog land known as the Great Black Swamps.