Mantleray’s paraphilia provides a hearty dose of laughs, but the real comedy treasure trove comes out of his deeply screwed up relationship with his mother, Dr. Greta Mantleray (Sally Field), a world-renowned psychologist whose personality and voice are the basis for the AI system that runs the drug trial.

Greta’s history with therapy and James’ preference for neurochemistry is a constant source of comedic tension between the two. Theroux and his mother also share a real-life occupation (both are writers), but the actor told Quartz that Greta and James’ mother-son relationship is certainly not based on his own family. “We actually have a very good relationship, so there wasn’t much to draw on there,” Theroux said of his mom. “She’ll get a kick out of it.”

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Image: Netflix

Before the character appears, the audience encounters him via a video introduction. To record it, Theroux insisted on using a teleprompter, and having the teleprompter not work properly so that it would make the character’s line readings seem more genuine. ”I didn’t want the teleprompter person to be great at it,” he said. “I let the fuckups happen.” Theroux achieved what he wanted: Mantleray’s stilted, nebbish reading is a hilarious microcosm of the character.

Theroux’s deadpan delivery of phrases like “globular cluster of arborized realities” is perfect, painting Mantleray as someone extremely invested in his life’s work, even if it doesn’t make a lick of sense to literally anyone but himself. He’s clearly intelligent, but comes across like an insecure man-child, unaware that his ridiculous wig and off-putting affect only make him seem even more desperate.

“The more you try and present as a strong character, the weaker you come across,” Theroux said. “It’s like political leaders who have the appearance of being tough guys when really they’re the most vain, insecure people on the planet.”

This is far from the first time Theroux has displayed his comic genius on screen. He appeared in Zoolander and wrote the script for Tropic Thunder long before he ever starred in HBO’s The Leftovers, and is an underrated comedic presence who consistently demonstrates an ability to not take himself too seriously on or off camera. Played by a lesser actor, Mantleray could have become a complete caricature of an actual human being, but Theroux grounds him in a sense of humanity that is at once endlessly amusing and, oddly, sad.

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