In a world where time becomes a weapon and reality bends at the will of a select few, the mind-bending journey of Tenet left audiences captivated and craving more. As the credits rolled, viewers were left with a sense of wonder and curiosity, yearning for an alternative ending that could further unravel the intricate layers of this mind-boggling masterpiece.
Well, dear readers, your search ends here.
Brace yourselves for a thrilling exploration into a new realm of possibilities, as we present to you the alternative ending to the Tenet movie - a conclusion that will challenge your perceptions and leave you questioning the very fabric of time itself.
Welcome to a world where the impossible becomes possible, where the future is not set in stone, and where the fate of humanity hangs in the balance.
Get ready to embark on a journey like no other, as we delve into the depths of Tenet and rewrite its destiny.

The new ending
As the final battle between the Protagonist and Sator reaches its climax, a sudden twist occurs. Instead of the Protagonist successfully preventing the activation of the Algorithm, Sator manages to activate it, plunging the world into chaos.
The Protagonist, devastated by his failure, is left to witness the destruction unfold.
However, as the world crumbles around him, the Protagonist discovers a hidden message from Neil, his loyal ally. It reveals that Neil, aware of the Protagonist's impending defeat, had devised a plan of his own.
Utilizing the inverted technology, Neil had secretly traveled back in time to plant a failsafe device within the Algorithm.
With newfound hope, the Protagonist embarks on a desperate mission to locate the failsafe device. He must navigate through inverted time, facing mind-bending challenges and encounters with his past self.
Along the way, he unravels the true nature of the Algorithm and its purpose.
As the Protagonist finally reaches the failsafe device, he realizes that it holds the power to reverse the effects of the Algorithm. However, using it would come at a great cost. The Protagonist must sacrifice himself, erasing his existence from the timeline, to activate the failsafe and restore the world.
In a heart-wrenching moment, the Protagonist makes the ultimate sacrifice, triggering the failsafe device. Time begins to unravel, and the destruction caused by the Algorithm is undone. The world is saved, but the Protagonist is erased from history, leaving behind only the memories of those who knew him.
In the aftermath, the remaining characters, including Neil, find themselves grappling with the loss of the Protagonist. They are left with lingering questions about the nature of time, sacrifice, and the impact of their actions.
The audience is left to ponder the implications of the Protagonist's sacrifice and the legacy he leaves behind.
Questions for discussions

I have imagined other alternative endings; check the link below or in the sidebar.
Tenet story / Synopsis + complete story - DR1 2020
Tenet explained / Understanding the ending and story - DR1 2020
Unlocking the Secrets of Time: A Mind-Bending Thriller That Will Leave You Breathless - DR1 2020
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