Can you explain the twist in tenet?

The only verified information from the Wikipedia excerpt describes Tenet as a 2020 science‑fiction action thriller written and directed by Christopher Nolan. It follows a CIA officer who is recruited into a secret organization and tasked with tracing the origin of objects that are traveling backward through time and their connection to an attack by the future. No specific plot twist or explanation of one is mentioned in the supplied evidence, so an accurate description of a twist cannot be given.