Some situations just call for a few psychopaths. They have limited emotional responses, no empathy, and they thrive on danger. When the situation calls for a fearless action hero, look no further. But what do you do in the 28th century when you desperately need psychopaths, but you've long since eradicated the condition? Fortunately, you have time travel. When you need some real live movie action heroes but there are no psychopaths available, you simply go back in time to medically "manufacture" them, so to speak, so they'll be grown, trained and ready to report to work today as "Rambo." In the year AD 2754 the world's population lives in oceans across the globe and the time continuum. They have been living alongside of us and observing us since the beginning of time. Their world has no hunger, or countries, or religion, and they designed the new world order to prevent another war.
Their world is the same world John Lennon described in his song, "Imagine."
In that future there also are no more history books. Instead, Historians travel back in time to attend historically significant events, then report on things as they actually happened, not has traditional history has always told us they happened. Then they upload these reports to the Educator Database, which 28th century history teachers use to create their course curriculum.
One Historian unthinkingly and illegally says two words to two AD 2021 "locals" in a misstep that could potentially trigger a disastrous alternate history. To repair this "Anomaly" and return the time continuum and recorded history to its original state, 28th century world leaders gather an emergency team, which includes one regular Historian, a local psychologist, and four psychopathic Historians, called "Heroes," whom they dispatch to do the dirtiest jobs.
It will take more than four action heroes to put the time continuum back into place. Historian Avid must learn and then teach 28th century psychotherapy techniques to psychologist Helen. They all hope that she can now dissuade her disturbed client from murdering an adolescent who is supposed to grow up to be a highly consequential historical figure. Those two careless words spoken by that other time traveler have now put the boy's life at risk, and threaten to change the future of the world.