In the story, Subaru Natsuki is an ordinary high school student who is lost in an alternate world, where he is rescued by a beautiful, silver-haired girl. He stays near her to return the favor, but the destiny she is burdened with is more than Subaru can imagine. Enemies attack one by one, and both of them are killed. He then finds out he has the power to rewind death, back to the time he first came to this world. But only he remembers what has happened since. 
 
(Source: Anime News Network)
 
Notes: 
- The first episode aired with a runtime of ~50 minutes as opposed to the standard 25 minute long episode. 
- In the Winter 2020 season, Re:ZERO was rebroadcast and re-edited to fit into an hour time-slot. This edit included the first OVA and added slight modifications to certain scenes throughout. It also added an additional scene at the end of the final episode.

White Fox

Funimation