Nearly a century after climber George Mallory vanished on Mount Everest, a pair of explorers are recreating his expedition to find out what really happened. But the Turner twins are putting their twist on history: One of them will be wearing Mallory’s 1924 gear, while the other is outfitted in today’s cutting-edge equipment when they climb Nepal's Mera Peak. Their journey, backed by scientists, could reveal whether Mallory’s clothing was strong enough to have carried him to the summit.