The Emmy-winning actor said he believes he got sick after directing a play in London last December

Brian Cox is opening up about his personal experience with the novel coronavirus.

While appearing virtually on The Late Late Show with James Corden, the 74-year-old Succession actor revealed that he previously had COVID-19 but didn’t know until he later tested positive for antibodies.

"I'm a diabetic, and I went from my usual bloods that I usually have between months," Cox told host James Corden. "I went there, and they took my bloods, and they took the COVID test. Then my doctor called me and said, 'Oh, congratulations. You've had it.' "

The news came as a complete shock to Cox, who said that he had "never felt anything," which prompted him to ask his doctor how he contracted COVID-19.

Brian Cox
Brian Cox
| Credit: Jim Spellman/FilmMagic

Asked to list his symptoms, Cox could not remember having any of the major ones attributed to the virus — including shortness of breath and fever — but he did recall being sick last December while in London.

"I remember, I directed a play with my wife in London in December," he said. "And I remember coming here, and for about four days, I had these sneezing attacks. Just sneezing."

The Scottish actor said that he also experienced some tiredness, which he attributed to jet lag at the time before he shared that his doctor revealed that other COVID-19 patients had similar symptoms.

"The doctor told me that three of our patients had also these sneezing attacks, and that is an unknown symptom of COVID," he said.

Succession cast
Succession cast

Also in the interview, Cox discussed season three of his hit HBO series and shared his hopes that the show will be able to start shooting soon after it was delayed amid the ongoing health crisis.

Keeping quiet on what Succession fans can expect for the third installment of the comedy-drama, Cox did reveal however that it’s "jolly exciting."

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"I was on my way ... back to the states and [series creator] Jessie [Armstrong] called me in and said 'Should we talk of our next season?' And I said, 'Well, yeah' and he said, 'Do you want to know what is happening?' I said 'What do you mean, you have never told me what's happening, ever,' " he shared.

Cox added: "He said, 'I think you should know,' I said, 'Well, that's very nice of you Jessie but I'm not sure if I can deal with it,' but he told me what was happening."