"Tyrant" "had been out there for some time and, for whatever reason, they had not cast it."
The son of a British father and an American mother, the actor, who has "no ethnic connection to the Middle East that I'm aware of," plays Bassam "Barry" Al-Fayeed, a pediatrician who's living a very American life with his family in Pasadena, Calif. - where, coincidentally, this interview took place - when a family wedding draws him back to the country his father has ruled for decades.
"I thought it was ludicrous because [Barry's] an Arab and appeared to be older than me. And my manager and I discussed not even bothering with it," said Rayner, who at 36 is likely a few years younger than his character, a doctor married to another doctor (Jennifer Finnigan) with whom he has teenage children.
"I'm a TV 40-whatever," he said. "And Jennifer's a very TV-40," he added jokingly. (Finnigan's reportedly 34.)
"I thought it was crazy, but we pursued it and very quickly it got serious. . . . The ethnicity was also something they weren't too worried about" since the character had a non-Arab mother [Alice Krige], and because creator Gideon Raff's inspiration for the character was Syria's president."
Also a doctor, Bashar al-Assad was partly educated in Britain before returning home, succeeding his father and becoming one of the world's most notorious dictators.
"You only have to look at Bashar Assad, who's an Alawite [member of a Syria-based sect of Shia Islam] to see that, yeah, there are light-skinned, blue-eyed Arabs," Rayner said.
"I'm dual American-British. I'm familiar with having a foot in both camps, but not to the same degree," he said. "And if I was an Arabic actor looking at this, it would probably piss me off."
Though "The Godfather" was likely another inspiration for "Tyrant," in which a younger son who'd fled his family's bloody legacy is pulled back, Rayner insisted there's a "difference between Barry and Michael [Corleone].
"I think Michael, when we meet him at the beginning of 'The Godfather,' he's an extremely self-contained man. He knows who he is. He just hasn't figured out his direction yet. Barry is having an identity crisis. He really doesn't know who he is, at the beginning of the show."
"Tyrant" offered Rayner the opportunity to show "the entire reversal of a character," he said, likening it to Walter White's journey in "Breaking Bad."
"I'm not an actor who was sifting through lead roles in pilots, deciding which one to do. This is the one you dream about and wait for and wait for and wait for, and you don't get most of them, and then your number comes up and then, you know, it's a happy day."
On Twitter: @elgray