Ordinary junior high school student Bon Namihira encounters Time Patrol member Ream Stream, a girl from the future, along with a strange creature called Buyoyon. The Time Patrol agents save those who died unfortunate deaths that don't significantly alter the course of history. During these missions, anyone who sees Ream and the other agents has their memories erased. However, Bon's memory remains mysteriously intact, so he is brought in as a Time Patrol agent-in-training. Teaming up with Ream to carry out missions, Bon is excited about using tools of the future, including the 'time boat' that can sail through time and space. Bon gets carried away at times, but through the missions, he touches the lives of people who lived wisely in each era. Go on an epic journey throughout Earth and the history of humanity along with T・P BON!