Everything you'd want to know about Barbieheimer, the summer's hottest trend

It's July, which means it is also the month of Barbieheimer!

Light off some fireworks and don some pink because, in a little over a week, both Barbie and Oppenheimer will hit theaters. On July 21, these highly anticipated films will debut on the same day — and the world may never be the same. It's the movies, as God, Mattel, and Robert Oppenheimer intended.

But here's a little rundown in case this portmanteau has you scratching your head.

What is Barbieheimer?

If you are not, as the kids say, very online, you may be asking yourself, "What the hell is Barbieheimer?" Well, my friend, let me tell you — it is the cinematic event of the century. Not since Darth Vader told Luke that he was his father have we had a movie moment quite like this.

Barbieheimer is the mash-up of two films, Greta Gerwig's Barbie and Christopher Nolan's Oppenheimer. Some might say that a neon-pink Mattel toy and "death, destroyer of worlds" are counter-programming at its finest, but au contraire, cinephiles are here to tell you that the only thing that makes sense in this meaningless life is to see them both (preferably on the same day). While there are those that would paint this as a fierce rivalry, perhaps even a battle for cinema's soul, we prefer to think of it as an opposites attract rom-com.

As soon as people realized that these two highly anticipated movies (that are seemingly divergently opposed) were premiering on the same day, a new word was born — Barbieheimer. We believe it's listed in the dictionary as a synonym for perfection because Barbieheimer is the realization of the peak of human potential. It is, to borrow from another classic movie, the stuff that dreams are made of.

Is it "Barbieheimer" or "Barbenheimer"?

It's both, it's neither. Just like Barbie and Robert Oppenheimer, you can be whatever you want — a doctor, a prom queen, an astronaut, or even the inventor of the atomic bomb.

The thing about the internet is that no one agrees on anything and everyone wants to take credit for everything. Thus, the meme of this portmanteau has trended two ways — as both Barbieheimer and Barbenheimer. We suppose your preference is for whether you want to give more of the title to Barbie or Oppenheimer, but why choose when you can have both? (Though we draw the line at Oppenbarbie).

In the spirit of equity, Barbieheimer affords both films the same syllable count in the word.

What have the stars of Barbie and Oppenheimer said about Barbieheimer?

Just a reminder for when you're posting those thirst tweets that movie stars and directors read the internet too. Many members of the teams involved with Barbie and Oppenheimer have weighed in on the discourse about Barbieheimer. Imagine Christopher Nolan commenting on the Barbieheimer phenom — which he did! The filmmaker told IGN that he finds the obsession "terrific."

In a very "preserve the theatrical experience" type of way, he said, "Summer, in a healthy marketplace, is always crowded, and we've been doing this a long time. I think for those of us who care about movies, we've been really waiting to have a crowded marketplace again, and now it's here and that's terrific."

For her part, Barbie director Greta Gerwig is tickled pink by it all. "It's all love — double up, double up twice," she told The Hollywood Reporter. "I think you've got to see what the experience is, Barbie then Oppenheimer, Oppenheimer then Barbie. I think you've got to take all of the journeys."

Back in May, Matt Damon, who plays director of the Manhattan project, Leslie Groves, in Oppenheimer, was one of the first cast members to wade into the discourse. After Vanity Fair introduced him to the concept of Barbieheimer, Damon only had good will for both projects. "People are allowed to go see two movies in a weekend," he proclaimed. "Oppenheimer is one of them!"

Cillian Murphy, who plays the titular physicist in Oppenheimer, is similarly pro the double feature idea. "I can't wait to see Barbie," he told Spanish publication La Vanguardia. "I love Margot Robbie, I love Ryan Gosling, I want to see them now! I don't know what the debate is about, although it's not that I have an overwhelming opinion about it either. My advice would be for people to go see both, on the same day. If they are good films, that is what the cinema wins."

Even stars who aren't in either movie are getting in on the trend. Tom Cruise and his Mission: Impossible director Christopher McQuarrie encouraged fans to return to movie theaters this summer by posting photos of themselves with tickets for a Barbieheimer double feature.

However, Issa Rae, who features in Barbie, has some very specific thoughts about the order audiences should see the films. "[It's] hilarious," she told THR of the meme. "I love that there's solidarity though where people tried to pit us against one another, but now it's turned into like a double-feature situation. Obviously you should see Oppenheimer first and then cleanse your palate with Barbie. Oppenheimer is about an atomic bomb, people are gonna die. I want to end my weekend, I want to have mimosas and drinks and cocktails after Barbie, I don't want to like sulk."

What's the right way to watch Barbieheimer?

This brings us to the greatest question of our age — what order should you watch Barbieheimer? Is it better to start or end the day with Barbie? The internet is full of arguments for both preferences, but we're going to officially advocate for Oppenheimer first, Barbie second.

Look, we're journalists. We basically invented the concept of an all-nighter. We are not morning people. If we have to face our own mortality when we get up in the morning, we might as well do it while confronting the specter of nuclear holocaust too. Someone on Twitter suggested pouring yourself a cup of steaming black coffee and smoking a cigarette before you see Oppenheimer — and we endorse at least half of that (which half depends on whether our Health and Wellness officer is reading this). But let's be real, Oppenheimer is the hair of the dog — sobering and bracing in the utmost. It's a literal wake-up call.

Then, once you've plumbed the depths of man's capacity for evil, you can work through your existential crisis and your Oppenheimer-induced brush with nihilism with the aid of happy hour and some cosmopolitans ('cause they're pink, duh). Prepare your body to bathe in the magenta haze of Barbie. Ryan Gosling is just Ken, and you know what Ken? You're doing great, sweetie. Being just Ken is more than enough. Er, what's that? Barbie thinks about death too? Okay, maybe also book a reservation for post-Barbie drinks too.

Where can you find the best off-brand Barbieheimer merch?

Inside you there are two wolves and you need to let both of them out to play…

Just because Warner Bros. and Universal haven't teamed up on any movie swag doesn't mean there's not plenty of wardrobe options for Barbieheimer day. Designers on sites like RedBubble, TeePublic, and Etsy have created more designs than there are Barbie accessories.

We're big fans of this one, which features Barbie watching the pink mushroom cloud of the atomic bomb. It almost has Asteroid City vibes if you want to throw in another summer movie. Here's a similar take on the mash-up, this one with tons of t-shirt colors.

TeePublic also has plenty of Barbieheimer swag, including this t-shirt that conjoins Barbie and Oppenheimer's faces. If you want to get into the Frankenstein-assembled-parts nature of this odd mash-up, how about a Barbie t-shirt and an Oppenheimer t-shirt literally sewn together?

If you want something a bit more subtle, how about a baseball cap featuring Oppenheimer's famous cribbed quote, "Now I am Death, the Destroyer of Worlds" in the jaunty pink Barbie font? Might as well look cute while expressing your existential dread.

How are people embracing Barbieheimer?

Lest you think this is some internet trend with no application in the real world, think again.

Besides the aforementioned merch and buy-in from the stars of the movies, Barbieheimer is reaching the box office too. Variety reported that AMC Theaters has already sold over 20,000 same-day tickets for Barbie and Oppenheimer, suggesting that a not insignificant number of people are preparing to do the ultimate double feature. All that could add up to an awful lot of Barbie dream houses in ticket sales.

Whether you're the kind of person to think pink or one who walks around with a (mushroom) cloud hanging over their head, you can't deny the power and influence of Barbieheimer.

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Related content:

• Even Tom Cruise is planning a Barbie and Oppenheimer double feature
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• Greta Gerwig on how old Hollywood and disco inspired Barbie