Wu Yu is a math major, but works as mechanic, while Tan Jiao writes mystery novels for a living. Couple meets by accident, when Tan Jiao needs to fix her car. However, she has the overwhelming impression, that they have met before. Only then, she realize that she has a year of life, completely removed from her memory. Soon, it turns out that the key to her lost memories may be a ship's voyage. The same cruise she and Wu Yu met on. From then on, couple tries to recreate the course of events from that time, which is even more difficult. by the fact that Wu Yu himself has no recollection of time spent on the ship. The couple, however, have good reasons to uncover the truth ,when it turns out that this tour is the key to discovering who murdered Wu Yu's sister. Soon, thanks to the ability to travel in time, both of them, are trying not only to recover their memories and save the man's relative, but also to understand why they found themselves in this situation, in the first place.