When NASAastronaut Theodore Harris was in space the first time on September 16, 1963, it didn't go quite as planned. Alone in his Mercury capsule, he panicked and aborted the mission when a mysterious violet light penetrated the cockpit and began enveloping his body. In the investigation that followed, no evidence could be found to support his story, leaving a blot on Harris' NASA record and his life in ruins.
And now, at age 63, he knows he can never make amends with his estranged wife Madelaine, but he feels that he could clear his name if he could just get back to where he saw the light. When NASA turns him down, Harris is recruited by Carlton Powers, a self-made billionaire who plans to privatize space travel and thinks Harris' presence on the inaugural flight (on his new Daedalus spaceship) will help him sell the service.
Harris and Power are joined on the flight by Martin Reese, a skeptical tabloid reporter, Lil Vaughn, an eccentric fashion mogul and Ty and Barbara Chafey, young newlyweds who won a contest to travel on the space plane. But none of the Daedalus passengers know that Harris has reprogrammed the flight plan to take the flight to the site of the close encounter that shattered the young man's life.
When they reach the location, Harris heads out in a spacesuit without a tether and encounters the mysterious light again. This time he isn't afraid and learns the truth: the light never meant him any harm, it simply came to Earth to study humanity but never to interfere with it. As a gift, the light sends him back to 1963 but changes things so that he successfully completed his mission, giving him another chance at life and another chance to be with his wife.