. ♪ david couturi is one of them. >> a little over on the entry.he most nerve-wracking. >> reporter: this is the red bull cliff diving world series. 22 athletes, six events and one way out. a 90-foot plunge into frigid darkness. david's journey began on another coast. training for months in california. >> two, three. >> reporter: the grueling physical demands on a diver have dominated his life since he was a little boy. now his own body can meet a challenge. david is fighting back from a shoulder injury that stole last season from him. >> it was long and tough and nerve-wracking and mentally strenuous. it's been a long recovery road. >> reporter: across the country in indiana, a different challenge for a gymnast turned diver. >> i'm excited. i'm hoping this will be my year. >> reporter: cecily carlson will be one of the first women allowed to compete at the serpent's layer. -- lair. >> if even one thing goes wrong, that can be a big setback. >> reporter: we've come all the way to dublin, a three hour drive, and now it's amazing. we made it to the g