Brian Cox as Logan Roy in "Succession."
CNN  — 

“Succession” star Brian Cox has received accolades and awards for playing media mogul Logan Roy, but the actor said the role has left him with one unfortunate new habit.

In an interview with SkyNews for the Edinburg TV Festival, Cox said Logan has had a “terrible effect” on him.

“I was not really a swearer until I played this role and now I swear all the time,” Cox said. “It’s catching, it’s infectious.”

The patriarch of the Roy family is known for searing, profanity-laced monologues on the HBO drama, which is nominated for 25 Emmy Awards.

“Logan is quite a fascinating character because he’s so mysterious, we don’t really know how he thinks,” Cox said. “We know how he acts. We don’t really know how he feels.”

That sense of mystery extends to the upcoming fourth season of “Succession,” as Cox would only reveal a few general plot points.

“I mean, we do our stuff, we’re still sorting out what we do with the children and are they going to behave themselves and are they going to learn anything?” Cox said of the Roy family when the show returns. “We’re trying to secure the firm. And that’s really what we’re continuing to do.”

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