Shark Week airs Sunday through Saturday at 4 p.m. on Discovery Channel.

After all these years, what could possibly be left to say? Sharks, efficient eating machines with an ever-ready supply of new teeth, ferociously kill, and sometimes the gory deaths are documented.

Yet, it seems that the public's fascination with the toothy terrors of the deep and Discovery Channel's ability to plumb whatever depths necessary to find new angles are endless. And for this, the 20th anniversary of Shark Week, beginning Sunday, July 29, the cable channel manages to put a new spin on these ancient creatures with more than 130 hours of shows.

Les Stroud, the station's intrepid Survivorman, hosts the week-long series of specials. Stroud is delightfully enthusiastic about sharks, even though he was once bitten.

For a guy who finds shelter in caves, it seems incongruous talking to him in the gilded lobby of Manhattan's Ritz-Carlton, where he pours Earl Grey tea from a china teapot.

"It's brilliant," Stroud says of swimming with the sharks. "I've always been confident and comfortable with wild animals. The first time I went down (on a dive) in the Caribbean, I had 25 sharks around me."

He says this with the sort of gleeful awe that others would use if they went to a butterfly exhibit and swarms of monarchs fluttered nearby.

"They are no different than other wild animals," Stroud says. "They're just animals under water. Lions, bears, sharks, there's a way to deal with all of them."

Two weeks earlier, the Canadian adventurer took his first deep-sea dive. Of facing sharks, Stroud says, "Look, I get it. You can rip me apart! I know that and you know that. I just want to touch your dorsal fin."

10-foot hammerhead

And in the same sort of hitching a ride that tourists do with dolphins, Stroud sliced through the water while holding onto a 10-foot hammerhead. "It feels like a hard piece of rubber, with sandpaper on it," he says. "It was profound and addicting."

As cool as Stroud finds sharks, he certainly wouldn't have made it to 45 doing what he does had he not taken precautions. Stroud will offer safety tips during the week. His first is to remove all that glitters before diving in.

"Lures are shiny metal," Stroud says. "Jewellery is shiny metal. It will bring attention from something small, and that will bring attention from the next level. So, one of the tips is to be a little drabber dressed if you don't want to get eaten in the ocean."

The next tip, which he says is "extremely difficult" to do is, "Never let them out of your sight. The way a shark will attack you is from behind."

The next safety tip is hardest: Stay calm. "They sense fear," he says. Undoubtedly, but when sharks circle, finding that Zen moment could prove impossible.

"If you are panicking and thrashing about, that excites them," he says. "The worst thing you can do is turn and swim. That just indicates that you are prey. Never run from a lion or a bear. You are supposed to stand there, much as you will have to change your underwear. It is easier to face a shark. If you are watching them, they might not attack."

Still, there are no guarantees. In the kickoff two-hour special, Ocean of Fear: The Worst Shark Attack Ever, Richard Dreyfuss (Jaws) narrates the harrowing story of the USS Indianapolis. After the vessel was torpedoed on July 30, 1945, in the Philippine Sea, hundreds of sailors were burned and tossed into the water as sharks moved in.

Deadly Stripes: Tiger Sharks, on Monday, July 30, shows South African shark expert Mark Addison diving without oxygen to swim around 20-foot, 1,300-pound tiger sharks. They're mesmerising as they glide through the crystal waters off Aliwal Shoal.

This type of shark has been known to devour full coats of armor, but Addison says he's intent "on finding out what makes tiger sharks tick."

Actual shark attacks

If one has ever wondered just what horrors occur when sharks strike, tune in Monday for Top 5 Eaten Alive. Sensitive viewers be warned: This features footage of actual shark attacks; it is bloody and scary.

Heather Boswell, working on a research ship 2,000 miles off the coast of South America, was swimming when a great white shark ripped off her leg.

She was relatively lucky - it was a clean bite, her colleagues remained calm, and she was airlifted to a military base, where doctors saved her life. Other stories are equally chilling.

In Shark Feeding Frenzy on Tuesday, July 31, Stroud tries to determine which of seven species has the strongest jaws. Perfect Predators on Wednesday, August 1, offers more of that screen-saver stupor as we watch these enormous animals gracefully move through water and scientists attach cameras and tracking devices to them.

Thursday, August 2, Dave Salmoni, a frequent host on Animal Planet shows, checks out New Guinea's shark whisperers in Shark Tribe. In Sharks: A Family Affair, on Friday, August 3, shark expert Craig Ferreira takes his family on a shark-studying expedition. The premieres end with the Saturday, August 4, Sharkman as shark expert Michael Rutzen tries to hypnotise a great white.

Among reasons people watch the specials is the tension. The threat of being bitten lurks constantly.

Stroud was bitten. He leans over to show off a slight scar on his hand.

"I hand-fed a 10-foot lemon shark," he says.

Why hand-feed a shark?

"It was part of the show," he says, an impish grin spreading across his stubble. "It's the interaction of what causes a shark to attack. I was feeding 25 sharks and paid attention to the wrong one."

"He broke a tooth on my hand," he says, not bothering to repress his laughter. "By the time I got home to Canada, (the story grew so) I had lost my leg."

"I wasn't scared at all when he bit me," Stroud says. "I gave him a right hook. I knew that shark didn't want me."

- Jacqueline Cutler, Zap2it