The plot follows a secret branch of the US National Security Agency, which has developed a time travelling device based upon alien technology found at Roswell.

The backstep team and the equipment are stationed in a base in a secret location somewhere in the desert of Nevada called Never Never Land—a play on Area 51, or Groom Lake Flight Test Facilities, also known as Dreamland.

They search for a test pilot, eventually selecting Frank Parker, a former Navy SEAL and CIA operative whose son died in the aftermath of the attack, to be the world's first "Chrononaut".

[1] Original cast member Sam Whipple, who played Dr. John Ballard, left the series four episodes into the third season, due to diagnosis of a cancer that was eventually fatal.

[1] Justina Vail, who played Dr. Olga Vukavitch, quit the series before the end of the third season, though she agreed to film a few extra scenes to wrap-up her character's arc.