Astronaut Jack North is hit by mysterious solar radiation while photographing an eclipse during a spacewalk. Returned to Earth, scientists find that as long as his eyes are exposed to the ultraviolet in sunlight, his mental and physical abilities are boosted to superhuman levels. More than a few minutes of exposure risks overload and death, so he needs to wear special sunglasses. Wearing the glasses or at night, he’s a normal human. But in sunlight, he can think like a computer, recall everything, has super-senses and super-strength and can run as fast as a motorcycle. North uses his newfound abilities to investigate the murder of his best friend and fellow astronaut.