"A curious historian and an adventurous archaeologist discover a portal to different time periods, leading to a race against time to restore the timeline and prevent a catastrophic future, only to realize that the portal was created by a future version of the protagonist, leading to a mind-bending realization about the nature of time and their own destinies."
Protagonist: A curious historian who is fascinated by the idea of time-travel; Deuteragonist: An adventurous archaeologist who helps the protagonist navigate the different time periods they encounter.
The protagonist discovers that changing events in the past has unforeseen consequences in the present, leading to a race against time to restore the timeline and prevent a catastrophic future.
In the end, the protagonist and deuteragonist successfully navigate through different time periods and manage to restore the timeline, preventing a catastrophic future. However, they decide to keep the portal a secret, knowing the dangers of altering history. The protagonist continues to study the portal and its implications, while the deuteragonist returns to their archaeological expeditions.
Twist: As the protagonist and deuteragonist restore the timeline, they realize that the portal was actually created by a future version of the protagonist, leading to a mind-bending realization about the nature of time and their own destinies.