With silvery mane and billowing robes, Will Geer strides across the leafy natural amphitheater in California's Santa Monica mountains like a road-company vision of God. While most men his age are looking backward to Medicare, the 72-year-old Geer, TV's crusty Grandpa Walton, is playing patriarch to a troupe of actor disciples. Amateur and professional, working and destitute, and, nepotistically, four of his own seven children, they come to join him in a celebration of Shakespeare.

For decades Geer has been fighting the restrictions of the conventional theater by recuiting a pickup company of actors and folksingers and spending a season on tour in the sticks. Until recently, the troupe traveled in Geer's own customized Greyhound bus, but the cost and scarcity of fuel and The Waltons' scheduled summer-long filming have this year kept Geer from his odyssey. Flocking to the rock-rimmed stage he has built in rugged Topanga Canyon, five miles from the Pacific Ocean, his apostles perform with Geer on the weekends.

Himself a nomad in the tradition of his late folksinger friend Woody Guthrie, Geer has spent much of his life roaming back and forth across America, performing wherever he could find an audience. A veteran of showboats, tent shows, urban loft theaters and vagabond stock companies, he is impatient with less energetic and volatile actors. "The important thing isn't where are you studying but where are you playing?" he erupts. "Are you doing some Shakespeare? Are you doing some classics? Are you learning a poem every day of your life? Are you capable of doing a sonnet in one breath?"

The beauty of his free outdoor theater, says Geer, is that actors are at liberty to extend their horizons without being dictated to. They can "bulge over, go over the edge, enlarge, do things they want to do, play love scenes in a state of tumescence, not just do what a director says. Anyone can come here on a Sunday and say 'I feel like playing Ophelia today,' or 'I feel like playing Romeo.' They'll let us know in the morning, then we'll go out and do it." What happens if more than one actor wants the same part? "Well," Geer growls cheerfully, "they fight over it."

Geer was born to a certain cantankerous anarchy. From a farm in Frankfort, Ind., he began moving around the country as a boy when his father went to work on the railroad. Later he earned a degree in plant and animal husbandry at the University of Chicago, a study he still puts to use by cultivating authentic Elizabethan gardens at Shakespearean theaters from Topanga to Stratford, Conn.

A lifelong radical, Geer was once married to Herta Ware, granddaughter of "Mother" Bloor, one of the founders of the U.S. Communist party. Invited to testify before the House Un-American Activities Committee during the Red scare of the early 1950s, he appeared resplendent in a dazzling red shirt and a purple plaid tie, and good-naturedly called the questions "hysterical." Afterward, he was blacklisted in Hollywood for years.

Somehow it didn't dim his natural free spirit. He runs a sort of bohemian cottage compound in the Hollywood hills during the TV season, and has another home on a farm in Connecticut, where he lives in a sort of informal connubial arrangement with a woman he calls his "next favorite" wife. His "favorite," Herta, divorced him years ago. As with all slings and arrows that have struck over the years, Geer chose to adjust gracefully. As he told a Topanga audience recently over the ear-numbing din of barking dogs, rumbling motorcycles and droning planes, "This too shall pass, but Shakespeare will goon and on and on."