It's a phenomenon known as the "Vegas death ray." A super-heated beam of highly-focused sunlight was reflecting off the windows of the Vdara hotel and burning sunbathers below.
William Pintas, a Chicago lawyer, told INSIDE EDITION his hair was actually singed by the so-called "death ray," and his plastic bag melted.
"If I had to guess, I would say the temperature had to be in excess of 160 to 170 degrees," said Pintas. "It was just so hot and I could begin to smell my hair burning, and I really couldn't understand why it was burning."
The Vdara is a Vegas hot spot. Authorities are blaming the energy efficient windows which are designed to reflect the sun's rays to keep the interior of the hotel cool. But the sleek curvature of the Vdara focuses the heat like a lens, sending the temperature by the pool soaring.
A Vdara employee warned an INSIDE EDITION producer not to stay in the death ray's hot spot, where you can see a plastic cup melting.
The employee said, "We've cleared the chairs from this area because it can get very intense right now."
The hotel's owners have provided more shade by putting out bigger umbrellas and more palm trees by the pool.