With its impeccable stagecraft, dramatic lighting, and a host of magical illusions, the award-winning play Harry Potter and the Cursed Child has been delighting theater audiences since its premiere in 2016. And whether you’re a fan of all things Harry Potter, a novice when it comes to wizards and Muggles, or somewhere in between, now you can step inside that theatrical world with the launch of Harry Potter and the Cursed Child Curtain Call, exclusively on Portal in the US and UK.

The Harry Potter and the Cursed Child Curtain Call experience lets you and up to three friends transform into characters from the play and bring the magic of the stage show to life during Portal-to-Portal video calls. In addition to Curtain Call, you can hangout with your friends in Hogwarts Great Hall, the Ministry of Magic, and the Edge of the Forbidden Forest during video calls or capture videos to share using Portal’s Photo Booth app. There are also 12 exclusive augmented reality (AR) masks of the most popular characters from the play available on Portal. No Portal? No problem. Fans on Instagram and Facebook can still interact with the AR masks via each app’s camera and share video and photos via Stories.

Anyone can initiate the experience by tapping “Curtain Call” in the effects tray on Portal. You can then select one of three locations from the menu to visit: Hogwarts Great Hall, the Ministry of Magic, or the Edge of the Forbidden Forest. When the lights come up, each person on the call will embody a character from the show with a unique spell, which is assigned randomly. Simply nod your head or tap the screen to cast it and watch as your friends marvel at the magic.

Callers can fully embody the characters thanks to real-time skin sampling that matches the 3D character to your unique skin tone before converting it into an AR mask for seamless integration. And this is one of the first times we’ve connected people’s AR experiences across screens in a collaborative, multi-participant environment, where everyone can experience the AR effects simultaneously.

All the AR masks and experiences are powered by Facebook’s own Spark AR, the same technology used by hundreds of thousands of creators around the world. We recently launched a version of this technology so AR creators can also build real-time social video calling experiences of their own. Our Multipeer API includes shared environments or contexts, synchronized effects, and even lightweight AR games.

The ability to embody the characters in AR is an important part of the experience. Similarly, so is honoring the on-stage experience in this digital format. To recreate the live theater experience on screen, we match key lighting cues from the production, relighting each caller in AR as if they were performing on the stage. “Lighting is an important component of visual storytelling in theater — it captures a mood and creates an aesthetic,” explains Art Director John Niehuss. “But it’s particularly important in Harry Potter and the Cursed Child in helping establish specific, iconic locations. Lighting is one of the primary things we could draw on to mimic the play in Curtain Call on Portal.”

All that dynamic lighting presented a unique challenge — you can’t currently add a lot of 3D lights to the Spark AR engine without a significant performance hit. The Creative Engineering team avoided that obstacle by using a shader-based “material capture” or “MatCap” lighting system (also known as a “LitSphere” approach). This let them use more lights than they could have normally. It also allowed those lights to be more carefully art-directed and managed by artists since the inputs were just little images of spheres with light direction painted onto them.

“We wanted to push the limits of what has been done with AR to deliver something truly unique for the passionate fans of everything Harry Potter,” says Niehuss. “And we’re honored to be able to bring some of the magic of Harry Potter and the Cursed Child into people’s homes.”

Spotlight on Story Time

In addition to Curtain Call, we’re adding new multiple choice stories to the Story Time library that will delight audiences of all ages. These new stories let the reader and audience make choices together and explore how those choices impact the story. Build a Story is a classic adventure where you get to choose the hero, setting, conflict, and resolution. Each choice you make defies expectations as you realize that looks can be deceiving. Last but not least, the Extra Ordinary Cafe lets you create your own multi-course meal by selecting the cuisine and each course. Each scene contains unique and absurd food as you open up to trying new things.

These new additions join fairy tale classics like Goldie and the Three Bears, Little Red Riding Hood, and Three Little Pigs as well as Pete the Cat, Llama Llama, and more in the Story Time library.

To learn more about what Portal has to offer, visit portal.facebook.com.