How William Jackson Harper went from The Good Place to the MCU with Ant-Man and the Wasp: Quantumania

William Jackson Harper is trading The Good Place for the Quantum Realm.

As the perpetually anxious Chidi Anagonye, Harper faced all sorts of absurd situations on The Good Place — from flying shrimp to pots of Peep chili to the jarring incomprehensibility of the Time-Knife. But his latest role might take him to even stranger places: The actor officially joins the Marvel Cinematic Universe with Ant-Man and the Wasp: Quantumania, starring as a grumpy telepath with a light-up forehead.

"I have been a huge [Marvel] fan since, like, forever," Harper, 43, tells EW the day after the film's Los Angeles premiere. "So for someone to call me to be in something like this, I'm like, hell yeah. It's an easy yes."

Harper stars as Quaz, a telepath living in the microscopic Quantum Realm. (His mind-reading abilities are automatic and involuntary — and his forehead glows whenever he hears someone's thoughts.) He and a small band of Quantum Realm residents are rebelling against Kang the Conqueror (a menacing Jonathan Majors), and eventually, they cross paths with Paul Rudd's Ant-Man and Kathryn Newton's Cassie.

Harper got the call from Marvel shortly after wrapping his HBO Max anthology series Love Life, and he says he jumped at the chance to join the MCU — even if he didn't know all that much about who he'd be playing. Still, he says, he quickly fell in love with the cynical Quaz, who proves that telepathy might not be all it's cracked up to be.

"It's a pretty great piece of writing: He's jaded because everyone's gross," Harper says with a laugh. "I love that. He's like, 'I didn't need to see that thought of yours. I really didn't.'"

With roles in The Good Place, Midsommar, and The Underground Railroad, Harper is no stranger to ambitious, high-profile projects. But once he arrived on set, he and his costars were stunned by the sheer scale and elaborate production design of the Quantum Realm — from talking buildings to extras dressed up as broccoli people.

"Just going into that world, my mouth was on the floor the whole time," Harper adds. "It's just legions of people working to make that world feel as vibrant and full as they can. Walking on, I was like, 'Wow, you don't have to fake much.'"

Ant-Man and the Wasp: Quantumania is in theaters now.

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