Time messenger Kate receives a doomsday letter signed by herself.
The instruction in the letter: destroy the "Time Messenger" project and prevent its birth.
She traced the source and found that she had already fallen into a time loop in the future, and every resistance led to a deeper doom.
With the help of the founder's daughter, Alison, they returned to the project's launch day.
Kate confronts her younger self, and Alison witnesses her father experimenting on another "self."
The moment they pressed the detonator, they understood at the same time:
The only price for ending the project is to erase all traces of the Time Messenger's existence.
