Meghan Markle
Meghan Markle was joined by the British security service on the set of "Suits" when she dated Prince Harry. Pictured: Markle attends day twelve of the Wimbledon Lawn Tennis Championships at All England Lawn Tennis and Croquet Club on July 14, 2018 in London, England. Getty Images/Clive Mason

Meghan Markle’s “Suits” co-stars recently revealed how they knew her relationship with Prince Harry was getting serious.

While speaking with Extra, Wendell Pierce, who played the role of Markle’s onscreen dad, said that he started seeing a guy from the British security service on set every single day.

“I actually didn’t believe it was real, then all of a sudden I turn around and there is this guy from MI-5 [British security service] on set every day,” he said.

Pierce also praised Markle for her role as the Duchess of Sussex and said that his co-star has been doing a wonderful job.

“The one thing that was clear, she was extremely happy… She had a glow. I knew she was in love… With the whirlwind of publicity and the world of being a royal now, the one thing that’s constant is the fact that I know she loves him,” he said.

Months ago, Pierce also talked about Prince Harry and Markle’s relationship on an episode of Harry Connick Jr.’s talk show “Harry.” He said that Markle has spoken about Prince Harry coyly while on the set of the hit USA Network TV series.

“She met this nice guy and we always talked about him in code really. You know, ‘How are you doing?’ ‘Oh, I’m going to London, coming from London, whatever,’” he shared.

Markle played the role of Rachel Zane on “Suits” for several seasons. But in November, she announced that she will no longer reprise her role. Around the same time, Markle got engaged to Prince Harry. The royal couple tied the knot at St. George’s Chapel in Windsor Castle on May 19.

“From all of us at USA Network and Universal Cable Productions, we want to send our most heartfelt congratulations to Meghan Markle and Prince Harry on their engagement. Meghan has been a member of our family for seven years and it has been a joy to work with her. We want to thank her for her undeniable passion and dedication to ‘Suits,’ and we wish her the best,” a statement from the network read.