Untangling the dual timelines of Oppenheimer (2024)

Oppenheimer was one of the highest-grossing and best movies in 2023, a critical and commercial success that led to the movie's huge big at the Oscars 2024.

Christopher Nolan's epic biopic about J Robert Oppenheimer is now available to watch at home, and some viewers might need a little bit of help untangling the timeline. In terms of Christopher Nolan's movies, Oppenheimer isn't as confusing as, say, Tenet or Inception.

However, given it's Nolan, the movie isn't a straightforward biopic about how Oppenheimer created the atomic bomb.

Oppenheimer messes around with time to split the story into two timelines with two distinct points of view, with the three-hour biopic cutting between both at will. And then just when you think you've got it all figured out, Nolan leaves you with an ambiguous finale that will have you thinking.

In case you are catching up now with one of the most talked-about movies of the past year, we're here to help by explaining the timelines of Oppenheimer and what that final scene means.

Like in Dunkirk, the two different timelines in Oppenheimer are established in the opening scenes. Here we've got "Fission" and "Fusion", with the former playing out in colour and the latter in black and white.

The other key difference, aside from the colour palette, is that "Fission" is J Robert Oppenheimer's (Cillian Murphy) subjective viewpoint and "Fusion" is a more objective view of Oppenheimer from the viewpoint of Lewis Strauss (Robert Downey Jr).

Within each timeline, there are also flashbacks which can muddy the waters somewhat and eventually the two timelines cross over with each other, so it's easier to focus on the main setting for each timeline.

The present-day timeline of "Fission" is in 1954, when Oppenheimer is taking part in a hearing that eventually leads to his security clearance being revoked. While we see this hearing play out, we get the flashbacks that take in everything from Oppenheimer's time at Cambridge through to the Manhattan Project and beyond.

Over in "Fusion", the present-day timeline is in 1959, when Strauss is at a Senate confirmation hearing regarding his nomination for the cabinet post of Secretary of Commerce (which the Senate declines to confirm).

As this plays out, we get flashbacks to Strauss's relationship with Oppenheimer, which started in 1947 when he presented Oppenheimer with an offer to be the director of the Institute for Advanced Study.

The flashbacks in either timeline don't play out sequentially, and Nolan skips back-and-forth over the timelines. We even see the same scenes, such as a public hearing in 1949 when Oppenheimer humiliated Strauss in reference to his grasp on physics, play out in both timelines.

In order to keep on track, you just need to pay attention to whether the scene is in colour or black-and-white. If it's the former, it's Oppenheimer's point of view and if it's the latter, it's Strauss's point of view.

That'll tell you whether it's a flashback from Oppenheimer or Strauss's hearings, and why there might be subtle differences you can spot in the repeated scenes. If you see either of them at a hearing, then it's 'present-day' for that timeline and everything else is a flashback.

Simple.

"Fission" does also jump forward to 1963 when Oppenheimer was given a scientific award by the US government, but thankfully this is just a one-off skip into the future.

It's Nolan, though, so you knew you were going to have to keep your wits about you.

After the Trinity Test is successfully carried out, the final act of Oppenheimer switches focus to the downfall of both Oppenheimer and Lewis Strauss.

Oppenheimer has his security clearance revoked after a campaign by Strauss, who had come to despise the physicist. However, this ends up backfiring on Strauss, as he isn't confirmed as Secretary of Commerce after a backlash by scientists to his treatment of Oppenheimer.

While in real life, their fraught relationship built over time, the movie frames it as stemming from one particular incident where Strauss believes Oppenheimer badmouths him to Albert Einstein.

The final scene of the movie cuts back to this moment when we finally hear what Oppenheimer and Einstein were really talking about – and it wasn't even Strauss.

Oppenheimer recalls how he sought out Einstein's advice when they were making the bomb to see if it could really destroy the world. Einstein questions why he's bringing it up and Oppenheimer replies that he believes they really did start a chain reaction that will destroy the world.

We then see Oppenheimer imagine several bombs being detonated around the world, but he's not talking literally. It's an illustration of the chain reaction that he believes started when he created the bomb which would, one day, lead to a nuclear holocaust.

A cheery thought to ponder in the credits.

For more Oppenheimer coverage, check out:

• Oppenheimer review
• How long is Oppenheimer?
• All 12 Christopher Nolan movies, ranked• Did Oppenheimer really know Einstein?• Oppenheimer is more Jewish than you realise
• What happened to Oppenheimer?

Oppenheimer is available to rent or buy now from Prime Video, iTunes, Microsoft Store and more in the UK.