What would you do if you could travel back in time and un-do what's been done? "Retake" follows a story about time travelers from the future and those whose mission is to keep close watch on them. Aratani Shinji has lost everything – his career, family and friends – as a result of the quirks of fate. As the head of the Census Management Section at the Ministry of Justice, he carries out a top secret mission direct from the Parliamentary Secretary for Justice to isolate time travellers, who have come from the future, at a dedicated residential area and put them under probation.