High in the Himalayas, Araceli Segarra lays an aluminum ladder across an icy crevasse. Actually, it's two ladders lashed together, a bridge that wobbles precariously when the crampons on her clunky boots clang against the rungs. She glances below into infinite space. You share the view, and gulp. "When you look down, you wonder how deep is that crevasse," says Segarra's voice-over. "Well, I don't want to find out." Your stomach is already making the trip.
Luckily, you're just a voyeur at Segarra's experience, sitting safely in a stadium-style seat at the Sony IMAX Theatre on Manhattan's Upper West Side. Your...