A Long, Long Time Ago is a novel by the pseudonymous jespah.
The story is told from the perspective of Richard Daniels.
On August 25, 3109, Daniels, a time traveler, is spending time with his girlfriend, Tina April, when he is contacted by his superior officer, Admiral Carmen Calavicci. Daniels is required to return to the Temporal Integrity Commission, as they are looking to hire more travelers and his opinion is requested. The entire setup is confidential, and Tina becomes dismayed when, yet again, he cannot tell her what is going on. Daniels deflects an argument and departs.
At the commission, there is a sudden change, and a candidate, Doctor Marisol Castillo's, scarf changes color, thereby signifying a change in the overall timeline. Rick is sent to February 3, 1959, in order to assure that rock musicians Buddy Holly, Ritchie Valens and the Big Bopper all die in a plane crash like they are supposed to, in Clear Lake, Iowa.
Meanwhile, the many job candidates are taken away via two shuttles. One travels without incident, whereas the other is forced to make an emergency landing on an inhospitable world, Berren One. The hard landing appears to have killed one of the candidates, Doctor Helen Walker. The others are beamed to safety.
While in 1959, Daniels sees a brunette chatting up the Big Bopper (JP Richardson), who is the linchpin around which most of the temporal changes revolve. Richardson, in the revised history, became a protectionist Senator, essentially taxing the British Invasion and killing off not only rock 'n roll music, but also the youth movement in the 1960s.
When the plane takes off and meets its fate, as it is supposed to, Daniels ends up comforting the brunette, not realizing that she is an enemy operative, the presumed-dead Helen Walker.