Two shark attack survivors faced their fears by swimming with sharks

ABC News

Hunter Treschl and Paul de Gelder.

Two men who lost limbs in shark attacks agreed to face their fears and dive back into shark-infested waters. Now, their story will kick off a week of shark-themed programming for Discovery Channel's 28th annual Shark Week, ABC News reports. 

Hunter Treschl is a student who lost his left arm while wading in waist-deep water on vacation. Paul de Gelder is a former Australian Navy diver who lost both his right arm and right leg during a military exercise. (Since then, Gelder has become a motivational speaker and Discovery Channel's resident marine conservationist.) The two first met last summer, shortly after Treschl was attacked. 

A few months later, de Gelder invited Treschl to swim with sharks once again - this time inside a protective cage. The teen agreed, and Discovery caught the encounter on underwater camera.

"It was a bit kind of scary at first," Treschl said on Good Morning America. "But that was like maybe the first two or three minutes and after that I really began to appreciate like, wow, these are some really cool animals and getting to see them up close is really awesome."

Their dive was part of a research project from expert Dr. Craig O'Connell, who's exploring the use of magnets as a shark repellent.  

"Sharks Among Us" airs tonight on the Discovery Channel at 10 pm eastern. Watch Treschl and de Gelder's entire interview with Good Morning America right here: