His strapping, 6'4" body now seems smaller and jarringly fragile; the hearty, engaging voice sounds measured. For all that, actor Christopher Reeve, 43, has never been so commanding a presence. Nor has he seemed more heroic onscreen than in his real-life recuperation from a riding accident last May that left him almost completely paralyzed from the neck down. "He is achieving astonishing things," says Robin Williams, who studied with Reeve at New York City's Juilliard School. Reeve has shown him, Williams says, "the sheer force of the soul."

The actor is still not sure what happened that day in Culpeper, Va., when his Thoroughbred, Eastern Express, halted suddenly before an easy, three-foot jump. According to Reeve, his hands became entangled in the bridle, so that he could not break his fall. He landed on his head, the force of his 200-pound body fracturing his first and second cervical vertebrae. The darkest moments came when he regained consciousness in the hospital: As he told Barbara Walters on ABC's 20/20 in September, "I suggested maybe I should just check out." Then he saw his wife, singer-actress Dana Morosini, 35, and his children, Matthew, 16, Alexandra, 12, and Will, 3.

During 24 weeks at the Kessler Institute for Rehabilitation in West Orange, N.J., Reeve made enormous progress. He underwent therapy for his legs; by November he was able to breathe for 12 minutes without a respirator. Using a motorized wheelchair, which he directs by puffing air through a tube, he attended two Manhattan charity events—most recently, a benefit for the American Paralysis Association. But on Dec. 13 came the achievement that meant most of all: Reeve spent his first night at home.

Such progress does not surprise friends like Williams, who says the actor brings a unique focus to any endeavor. "Now he's putting that same concentration into getting back," says Williams. "I think he will."