Hannah Fraser uses a handmade mermaid tail to help her <a href="http://abcnews.go.com/2020/real-life-mermaids-superhumans/story?id=10771939" target="external">dive to amazing depths</a>. This summer, she traveled with photographer and diver Cipto Aji Gunawan, who shot pictures of Fraser at a famed shipwreck site off the coast of the fishing village of Tulamben in Bali. Watch the full story Friday on "20/20" at 10 ET.

During the Bali diving trip, Fraser lucked into encounters with huge schools of fish. <p><p></p></p>

Fraser swims above a humpback whale off the coast of Tonga during the filming of an eco documentary, "Minds in the Water," scheduled to premiere in 2011.

Fraser calls her mermaid tails "work pieces of art."

Like Fraser, Linden Wolbert also uses a mermaid tail -- which was created especially for Wolbert by a special effects artist -- to explore the ocean.

Wolbert is shown here diving in Ben's Cavern in the Bahamas.

Remarkably, Linden can hold her breath for nearly five minutes.

Real-life mermaid Linden Wolbert swims with sharks. "When you do a long breath hold, your diaphragm begins to contract and that's telling you, 'Hey, you're supposed to be breathing,' and you have to learn to tolerate the discomfort of that feeling," said Wolbert. "And once you can achieve that, you can go for quite awhile."

Real-life mermaid Hannah Fraser swims with dolphins. "The tail gives me so much more propulsion and streamline ability," said Fraser. "I can swim much faster with the tail on than other people can without it."

Real-life mermaid Hannah Fraser swims with a dolphin. Fraser's fascination began when, at only 3 years old, her stick-figure sketches evolved into painting mermaids. It was only a matter of time before she told her parents that she wanted to become one -- for real.

Dean's Blue Hole in the Bahamas, where Linden Wolbert has gone to dive. The Bahamas has the fourth-highest drowning rate per capita in the world, and Wolbert is on a mission to save its children.

Real-life mermaid Hannah Fraser swims with whales. "Swimming with the whales was one of the most unbelievable, awe-inspiring experiences that I could ever imagine," Fraser said. "I had this moment where I'm swimming out in the middle of a huge blue ocean, complete depth, cannot see the bottom. Then there's this huge shape that just starts coming up -- it's like the size of a building!"

Special effects artist Allan Holt helped designed and built Linden Wolbert's mermaid tail. "It's roughly 35 pounds of silicone. The propulsion I get from this tail is immense. Everything is coming from my core, just like a dolphin," Wolbert said.

Special effects artist Allan Holt and real-life mermaid Linden Wolbert put the final touches on her mermaid's tail. After seven months and countless re-workings of the tail, Wolbert and Holt's unique partnership yielded a functional work of art.

Real-life mermaid Linden Wolbert crawling out of the ocean. "It's something that as a child, I would have been so just completely enchanted by," she said. "So I hope that I'm doing that for some other kids."