"Boston Legal" star William Shatner has revealed it was a kidney stone that sent him by ambulance from the TV set to a Los Angeles area hospital.

ADVERTISEMENT

The Emmy Award winner brandished a little black bag holding the offending stone during an appearance on "Live with Regis and Kelly," Zap2it.com reported Tuesday.

Shatner, 74, said he broke out "in a cold sweat" when struck by severe lower back pain while filming last Tuesday.

Looking back, Shatner marveled at "the purity of the pain," Zap2it.com said.

"They had to give me morphine. It was just unbelievable pain and it made you kind of think about what pain is. It was awful."

Passing the kidney stone added to the agony, he said. But, he added, he's feeling fine now with plans to go horseback riding this coming weekend.