Slow Horses Season 4's Saddest Moment Emerged Naturally From A Devastating Season 3 Scene [Exclusive]

This post contains spoilers for "Slow Horses" season 4.

The recently concluded fourth season of the spectacular Apple TV+ spy series "Slow Horses" continued to prove that it's one of the best shows on television, with the season culminating in a big revelation about River's parentage, a literally explosive climax, and a fatal shootout at Slough House. But one of the saddest scenes of the season comes just moments before the finale's end credits, when MI5 agent River Cartwright (Jack Lowden) moves his confused grandfather, former agent David Cartwright (Jonathan Pryce), into an assisted living facility because the man has been increasingly suffering so acutely from dementia. It turns out, the only reason it played out in that fashion was because of a different moment that happened in the previous season.

I spoke with the Emmy-winning showrunner of "Slow Horses," Will Smith (no, you'd probably have heard about it if that Will Smith won an Emmy for writing a British TV series), about this season, and I asked him if there were any performance moments from this excellent cast (which also includes people like Gary Oldman, Kristin Scott Thomas, Hugo Weaving, and more) that surprised him. He shouted out a few names, but gave particular props to Jonathan Pryce and explained how that devastating last moment between River and David came about:

"That final scene where River puts him in the care home, I went and wrote that off the back of watching Jonathan and Jack record this scene in series 3 where Jack has to go down to the Member's Club and tell him he's no longer a member, he's canceled his membership and he's just forgotten, and seeing how much sadness and pride and pain there was in the way they performed that, I could just feel, 'Oh, we can go even deeper, really, and sadder.'"

Pryce, a veteran performer whose credits include the "Pirates of the Caribbean" franchise, "Brazil," "Game of Thrones," "The Two Popes," and dozens more, was so convincing with his performance that he even managed to trick the showrunner into thinking he was about to blow a take. As Smith explained:

"Watching Jonathan do that and get to a place where he looks so lost in his eyes, it's so compelling that this character is in a mental fog and bits are coming to him and going. To the point where, he would do these pauses that'd be so deep that you'd literally think, 'Has he forgotten the line?' and then he'd be back in, and you'd be like, 'No, he's just a brilliant actor.' [laughs] But he so conveyed somebody that did not know where he was or what to say next that your reaction, as somebody who's watching it being performed and made, is, 'He's actually forgotten!' Of course he hadn't, but he just was so submerged in the part that that's how he made it feel."

The actor's commitment to the role pays off in heartbreaking fashion this season, as the penultimate scene of the episode closes with David practically begging his grandson not to leave him in the assisted living facility and River holding back tears as he walks away. "Slow Horses" is full of action scenes, terrorist attacks, and spycraft, but its greatest asset is how grounded it is; its characters aren't super spies, they're regular people who get injured and can die like anyone else. Any viewer who has experienced watching a family member slowly lose their mental faculties can relate to the emotional pain that both River and David feel in that scene, and the show's mixture of the grounded with the occasionally heightened continues to serve it extremely well.

/Film's Jacob Hall and I spoke about season 4 of "Slow Horses" on today's episode of the /Film Daily podcast, which also contains my full conversation with Will Smith:

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