Tenet is written and directed by Chirstopher Nolan. It is a Sci-Fi movie in which people from the future can communicate with the people in the present and even come into the past using devices called "timestile". The people from the future coming into the past are inverted and vice-versa. The conflict in the movie is about the annihilation of mankind. It's a race for survival.
The movie follows the story of "The Protagonist"(John David Washington) who is a CIA operative and he is caught in a mission and eats a suicide pill but survives as the pill is a loyalty test. He then learns about how the world is at risk and what these timstiles and inverted objects mean. He’s tasked with gathering more information on these inverted things and these events. In a way, he has the mission to save the world. We see The Protagonist travel with Neil (Robert Pattinson) and finally get to know that a Russian oligarch, Andrei Sator is being directed by the people from the future through time drops. He has cancer and doesn’t care if the world ends. His wife; Kat (Elizabeth Debicki) helps The Protagonist get close to Sator and even work for him. In a heist we see Sator knowing that he’s being spied upon and he shoots his wife and takes the artifact the future.
In the ending sequence we get to know that if different pieces of this artifact are put together it acts as a key to figure to the algorithm which has the ability to reverse the entropy of Earth and people in the future will be able to get their hands on this.
Sator will be using a dead man switch to ensure that this algorithm reaches the future. The Protagonist and Neil are able to take away the artifacts in time before Kat kills Sator. Ensuring the survival of the world. Neil in the end tells that The Protagonist and him are friends in the future, hence implying that Neil is from the future.
This movie is lost in its complexity and the conflict isn’t given much attention.