Bernie Mason spent World War II moving Army tanks, sometimes picking them up and setting them down with his bare hands.

He's not superhuman. And the tanks weren't some ultralight secret weapon.

It was combat trickery.

As a 21-year-old lieutenant, Mason helped lead a handpicked unit of artists and creative thinkers who deployed and arranged highly detailed, inflatable rubber tanks - and trucks, jeeps, and artillery - to fool the Germans into thinking the Americans had more firepower than they actually did or that the equipment was somewhere other than where it really was.

Officially, the unit was the 23d Headquarters Special Troops. Unofficially, it was the Ghost Army.

"It was like putting on a show," said Mason, of Wynnewood, who turns 93 in May.

A show, at least, until the Germans bought the deception. Mason had barely set foot in Europe in June 1944 when he found himself hugging the bottom of a foxhole as shells exploded all around, the enemy determined to destroy what it thought was a U.S. artillery emplacement.

Next month, Mason will be featured in a new PBS documentary that extols the unit's unique mission - making up fake divisions, sham headquarters, and illusory convoys in France, Belgium, Luxembourg, and Germany. The Ghost Army, written and directed by Rick Beyer, premieres at 8 p.m. May 21.

The men, as the film describes, were the Cecil B. DeMilles of the European Theater, drawn heavily from New York and Philadelphia art schools.

Beginning soon after the Normandy landings, through to the crossing of the Rhine, the 1,100 men of the Ghost Army used truckloads of inflatables and a cache of sound-effect recordings to create their performances.

The soldiers even altered their uniform insignia to match those of the units they were impersonating.

Trucks blared the noises of armored and infantry units. Radio operators broadcast false word of troop movements, knowing the Germans were listening. The inflatables - called "dummies" - were camouflaged as real machines would be, but in a way that made sure German observation planes would get a peek.

When dummies got hit by shrapnel, sagging as their air escaped, the soldiers patched and pumped them up.

The fakery was classified, kept quiet for decades after the war. Now the Ghost Army is getting wider recognition, though a dwindling number of its ranks are here to enjoy it.

"I was fascinated because it is so different than your typical World War II story," said Beyer, who first heard of the Ghost Army from the niece of a veteran, and who then spent eight years making the movie. "It's this weirdly different, absurd and yet unsung story."

Beyer liked how the tale played against the stereotype of rigid military thinking, showing officers and troops employing imagination and ingenuity. Several of the Ghost Army soldiers later became famous, including fashion designer Bill Blass and painter Ellsworth Kelly. Mason went on to a civilian career in portraiture and multimedia.

"My con artists," Ralph Ingersoll called them. As a staff officer, the author helped develop the Ghost Army.

The first mission began eight days after the Normandy invasion in June 1944 - with Mason in charge, the Overbrook High School graduate leading a 15-man force into France. Task Force Mason landed at a makeshift air strip at Omaha Beach, trading idyllic English countryside for war-ravaged shore. Mason recalls stepping past the bodies of German soldiers and the bizarre sight of a cow impaled high on a tree.

The task force set up phantom artillery a mile in front of the real 980th Artillery Battalion.

"They wanted to see if the concept of deception would actually work under battlefield conditions," Mason said in an interview in his home artist's studio.

The deafening German response convinced him it did.

The rest of the Ghost Army - camouflage, signal, radio, and combat-engineer components - caught up a month later, ultimately staging more than 20 ploys in Europe.

Today, films of the Ghost Army at rest look hilarious: A soldier casually pulls a truck over onto its side. Two men bat a tank turret around as though it were a volleyball.

"We had no real weapons," former Cpl. Al Albrecht told the filmmakers.

The goal was to make the Germans act - or not act - based on what they thought they saw.

In September 1944, the Ghost Army plugged a hole in Gen. George Patton's line on the Moselle River, the operation designed to look as though the Sixth Armored Division were moving in as reinforcement. The Ghost Army filled the gap for almost a week until the real Sixth Division arrived.

"There's evidence that the Germans bought some of those deceptions," Beyer said. "Particularly the last."

In March 1945, with the war in Europe nearing its end, the American Ninth Army prepared to cross the Rhine into the German heartland. The ghost troops were assigned to impersonate two full divisions to confuse the Germans about where the crossing might occur.

American casualties at the actual crossing point were low, and the film credits the Ghost Army.

When the European war concluded two months later, Mason was shipped Stateside to await orders for an expected invasion of Japan - made moot by the atomic bombings. He was discharged in December and headed home.

Mason worked 27 years as corporate creative director of Rollins Outdoor Advertising, then ran his own art business. In 1995, at 75, he graduated from Villanova University with a bachelor's degree.

He and his wife, Dottie, have been married 66 years.

In Mason's studio, a U.S. flag hangs on the wall, near his dog tags and a Bronze Star, awarded for meritorious service. On a desk is a book about the Ghost Army.

"Our mission was to draw fire on ourselves. I'm standing in front of one of these inflatables, and I'm wondering, which one of us is the dummy?" Mason said. "We like to think that by what we did, we were saving the lives of other people."