ひょんなことから新隊員としてタイムパトロールに加わることになった凡。先輩隊員のリームとともに歴史をさかのぼりながら、不幸な死に方をした人を救うという任務を遂行していく。

It's been nearly 30 years since Dr. Sam Beckett stepped into the Quantum Leap accelerator and vanished. Now, a new team, led by physicist Ben Song, has been assembled to restart the project in hope of understanding the mysteries behind the machine and the man who created it. Everything changes, however, when Ben makes an unauthorized leap into the past, leaving the team behind to solve the mystery of why he did it.