'Quiz' Star Matthew Macfadyen Still Isn't Sure If the Ingrams Are Guilty or Not

Quiz
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Michael Sheen as Chris Tarrant, Sian Clifford as Diana Ingram, Matthew Macfadyen as Charles Ingram - Quiz _ Season 1, Episode 2 - Photo Credit: Matt Frost/AMC/ITV

But did they do it? That question tugs at viewers' minds throughout Quiz, a thrilling three-part British drama written by James Graham and directed by Stephen Frears, which aired earlier this year on ITV (and finally reaches AMC on May 31), that examines a huge, real-life cheating scandal on England's ratings smash, Who Wants to Be a Millionaire?

In September of 2001, Major Charles Ingram, a former British Army major, and wife Diana (Succession's Matthew Macfadyen and Fleabag's Sian Clifford) were convicted of conspiring their way to win one million pounds. As Charles sat across from Millionaire host Chris Tarrant (Prodigal Son star Michael Sheen, who is nearly unrecognizable in his makeup), Diana and their alleged accomplice, Tecwen Whittock (Michael Jibson), would supposedly cough when the correct answers were read during the multiple-choice game show (So yes, you should mentally prepare yourself for three hours filled with various people coughing onscreen).

Sian Clifford & James Graham Tease 'Hysteria' Behind 'Quiz's True Story (VIDEO)See Also

Sian Clifford & James Graham Tease 'Hysteria' Behind 'Quiz's True Story (VIDEO)

Learn more about Charles and Diana Ingram who allegedly cheated their way to 'Who Wants to Be a Millionaire's top prize.

For the series' gameplay, a real hot seat — designed with built-in speakers so the sound would rattle contestants — was constructed. "It was sort of terrifying," Macfadyen admits. "They built it totally faithfully to the real thing. It was just brilliant."

To get into character, Macfadyen studied various documentaries on the infamous couple, and even watched a special 2003 Wife Swap episode the Ingrams participated in. He also sported a pair of fake teeth. "Our makeup designer Julie Kendrick suggested I have them, and I was a bit hesitant, and then she sort of persuaded me and she was dead right," he admits.

Quiz

(Credit: Matt Frost/ITV/AMC)

To this day, the Ingrams maintain they didn't cheat. Even the actor, who met the real-life couple on the final day of shooting ("They were really nice," he notes), is stumped as to whether the trio is guilty.

"Pretty much every single day, Sian and I would say, 'What do you think? Do you think they're innocent?'" Macfadyen recalls. "I came through the whole shoot, and I still don't think I've got it."

So that's not the final answer?

Quiz, Sunday, May 31, 10/9c, AMC