A spiritual adventure; BILLY CONNOLLY: JOURNEY TO THE EDGE OF THE WORLD THURSDAY, STV, 9pm.

So here's Billy, on the last leg of his 10,000-mile journey, half-naked, crawling on all fours, sweating like a man in a fever and barely coherent.

But Billy isn't ill, fortunately. He's just been reduced to an overheated blob by taking part in the sweat lodge ritual at the remote Canadian home of the Nisga'a tribe.

If extreme physical distress is the road to spiritual enlightenment, then Billy should be well on his way after he finishes his fourth session in the 'lodge' - a low tent in which the only light comes from the red-hot volcanic rocks giving off the heat - each session being hotter than the last.

The tribesmen throw water on the rocks to create an instant sauna. "In the end, the only way to get round the pain is to think it away," says Billy.

"It was one of the most difficult things I've ever done in my life... It's difficult to explain.

Oh my, oh my..."

Later, when he has gathered his thoughts, Billy looks back on his ordeal with a deep satisfaction.

He says: "I am closed off to anything remotely supernatural, or anything that mediums do, or ghost hunters and all that.

"I think it's all cobblers.

"But this was an out pouring of honesty and there's a beauty in it that has come to live with me and I hope it sticks around, because I rather like it."

CAPTION(S):

FEELING THE HEAT... Billy