Jack Lowden: MI5 agent River Cartwright chases danger, drama in 'Slow Horses'

Season 3 of Jack Lowden's "Slow Horses" wraps up Wednesday. Photo courtesy of Apple TV+
Season 3 of Jack Lowden's "Slow Horses" wraps up Wednesday. Photo courtesy of Apple TV+

NEW YORK, Dec. 27 (UPI) -- Dunkirk, Kindred and The Gold alum Jack Lowden says River Cartwright, the character he plays on the British espionage drama, Slow Horses, may have taken a beating this season, but he remains determined to get his troubled career back on track.

Set to wrap up Season 3 on Apple TV+ Wednesday -- and already renewed for Season 4 -- the show follows a group of MI5 agents who have been siloed to an outpost called "Slough House" after making huge mistakes on previous missions.

"He's been through a lot in every season so far. I think that River is going to go through a lot no matter what. Trouble seems to follow him. He chases danger and he chases drama," Lowden told UPI in a recent Zoom interview. "This is probably, physically, the most he's been through."

The show is based on Mick Herron's best-selling book series and co-stars Gary Goldman as River's sharp, but anti-social boss, Jackson Lamb; Jonathan Pryce as River's aging grandfather David Cartwright, a retired MI5 officer; and Kristin Scott Thomas and Sophie Okonedo as Diana Taverner and Ingrid Tearney, respectively, the current heads of MI5.

"They're wonderful to work with," Lowden said about collaborating with Oldman and Thomas.

Jack Lowden arrives on the red carpet at the "Dunkirk" New York premiere in 2017. File Photo by John Angelillo/UPI
Jack Lowden arrives on the red carpet at the "Dunkirk" New York premiere in 2017. File Photo by John Angelillo/UPI

"I didn't have much with Gary [this season], but I particularly enjoyed the few moments that I got to have with Kristin where she is telling me, 'I wish you hadn't happened at all,'" he said. "Getting a dressing down from Kristin Scott Thomas is definitely a bucket list tick."

Gary Oldman arrives for the North American premiere of 'The Laundromat' at the Princess of Wales Theatre during the Toronto International Film Festival in Toronto in 2019. File Photo by Chris Chew/UPI
Gary Oldman arrives for the North American premiere of 'The Laundromat' at the Princess of Wales Theatre during the Toronto International Film Festival in Toronto in 2019. File Photo by Chris Chew/UPI

Season 3 sees River largely out of the office, trying to steal an important file from MI5 headquarters to trade for kidnapped Slough House office manager Standish (Saskia Reeves).

Realizing this is all part of a bigger, more complicated plot, River is ensnared in MI5 politics and caught between agents who hate him and a dangerous private security firm.

Kristin Scott Thomas attends The British Academy Film Awards at the Royal Albert Hall in London in 2018. File Photo by Paul Treadway/ UPI
Kristin Scott Thomas attends The British Academy Film Awards at the Royal Albert Hall in London in 2018. File Photo by Paul Treadway/ UPI

The story features countless twists and turns and non-stop action, but Lowden said it was exploring River's interpersonal connections that excited him most about Season 3.

"His ongoing relationship with everybody and the development of how he sees everyone at Slough House [that were most compelling]," he added. "It was the relationships more so than the missions."

Sophie Okonedo attends the Winner's Room at the British Academy Film Awards at the Royal Albert Hall in 2019. File Photo by Rune Hellestad/UPI
Sophie Okonedo attends the Winner's Room at the British Academy Film Awards at the Royal Albert Hall in 2019. File Photo by Rune Hellestad/UPI

Although River is learning to work with his associates at Slough House, including Lamb, Standish, Louisa (Rosalind Eleazer), Roddy (Christopher Chung), Shirley (Aimee-Ffion Edwards) and Marcus (Kadiff Kirwin), he always keeps one main goal in mind.

"What he wants is to not be in Slough House," Lowden said.

"He wants to be the best at his job that's every existed -- better than his grandfather and prove to his grandfather that he is worthy of the name 'Cartwright.' How close does he get to it? I think he gets very close. He's always very close. I think he does everything he can, but a lot of things get in the way."

If River had his way, he would be doing important geopolitical work instead of carrying out mind-numbing, tedious tasks no one else wants to do at Slough House.

"He's forever trying to impress Taverner because she is where he wants to be," Lowden said. "He wants to work for her."

Lowden has mixed feelings about how accurate the show is compared to the machinations of real intelligence agencies.

"On one hand, I hope they don't operate like they do in Slow Horses, but, on the other hand, I'd love to know that they do, that they make constant mistakes," the actor said, referring to the agents' human fallibility.

"I imagine they make constant mistakes and they just have a very, very good public relations team or they keep it very, very quiet," he added. "I imagine they are very, very good, but I love thinking about them as some of these characters and thinking about them as real people."

The hardest part of doing this series -- for the cast and the filmmakers -- has been getting the tone right, since it blends high-stakes drama with dark comedy and action.

"It takes a while for everyone to find their feet and kind of collectively agree what the tone is and I think we are definitely there now," he said.

"We just have to keep it taut and keep it in a sweet spot and not be too relaxed or complacent about it, but just keep enjoying it, but just making sure everybody is still in the same show."