Interesting the first episode is very confusing. This makes it intriguing cause you’re going to try to understand everything in the coming episodes. Like a cliff hanger.
So in this series about time travel, the grand father paradox does not apply here, but instead parallel worlds collide. However, memories are altered, besides the main character. Being Sci-F you’re able to alter time travel so that you remember certain events. However, when the worlds collide, the worlds do not begin where he initially started the time travel.
IE he can sends texts to the past, but Let say he sends the text at 1pm, when the worlds collide where he is back in present time, he collided at 12 pm.
The first episode is confusing because he witnesses a murder, but she is alive 2 hrs later.
I believe in the ending episodes, his self went back that initially caused her death, then he went back again to save her.