Behind the Scenes: Sharp editing gets the best from Slow Horses

Mixing espionage intrigue with whip-smart humour, Slow Horses from AppleTV+ has burned through four seasons since 2022,  with Season 5 already shot and a sixth hotly rumoured. Adapted from author Mick Herron’s award-winning novels by See-Saw Films and screenwriter Will Smith, the drama revolves around a group of British spy misfits under the notional command of washed-up MI5 chief Jackson Lamb (Gary Oldman) who somehow manages to get mixed up in plots that endanger state security. Also starring in Season 4, adapted from Herron’s novel Spook Street, are Kristin Scott Thomas, Jack Lowden, Olivia Cooke, Rosalind Eleazar, Jonathan Pryce and Hugo Weaving.

In the editor’s chair for the first time is Robert Frost (BFE) who says he was already a fan of the show.

“Obviously having seen it you get a sense of what the finished product is like, who the characters are what their relationships are to each other but to prep for the Season 4 interview I basically blitzed through the books as well.

“I’m not a voracious reader but it was really helpful getting to know all the backstory for the characters,” he says. “Understanding who they are meant that I could talk really well with the director about what the story was and where it was going.”

One of the production’s hallmarks is that one director is handed responsibility for the whole six episode run. In this case it’s Adam Randall. Frost was invited to pitch by the executive producers of production company 60Forty who had made AppleTV+ miniseries Hijack on which Frost had edited.

Getting up to speed

“The audience just tweak straight away that something’s wrong” Robert Frost, Editor

Most viewers will probably not be new to the show at this point, so the filmmakers can play with a shorthand for re-introducing the principal characters, he says.

“One of the hardest things for this was the whole idea of pre-titles. For episode one, we have to get to the point where you believe that River has gone to his grandfather’s house and been shot.”

River (Lowden) is the action man of the series but nonetheless a sort of Keystone Cop secret agent. His grandfather (Pryce) is a former service chief but in this episode is revealed with dementia.

The beginning of episode two, cut by Harrison Wall, flashbacks to reveal what happened and in the process the two editors swapped some scenes around.

“Harrison took some scenes from the opening episodes and I inherited a couple from episode two,” Frost explains. “Originally in episode one, you saw River arrive at his granddad’s house, you saw him go into the house and you knew it was him, you saw that. Then you heard the gunshot.

“We realised that it was just too much of a fake-out to actually see River and then hear a gunshot, because we then don’t see a body. The audience just tweak straight away that something’s wrong. So, I ended up taking some scenes that were shot for episode two of the grandfather being lost in his own confusion and his sort of subjective sense of what happened with a figure that could be River coming in through the door. By mixing and matching those shots you sort of believe that grandfather was actually going to get attacked.”

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Frost also cut episodes three and five and this wasn’t the only incident of swapping around scenes. “When you’re building the first assembly of the episode, it seems inevitable that each scene is going to flow into the next but what’s fun as an editor is you can lift a scene and plug it back down and see how the story plays differently. Getting from one scene to another is always interesting too. For example, there’s a short scene where Lamb walks into a newsagents and he looks at frontpage headline story about the explosion. We found a way to cut from that picture of the suicide bomber to an image of him confessing on video and use that to then take us into MI5. Finding those pieces of connective tissue is fun.”

One handy thing about cutting a returning series is access to all the previous general shots of locations. Frost would add those in as a placeholders and then towards the end of the series, the camera would shoot some specific ones for the season to match.

“There’s quite a bit of traveling across London towards the end of the season so we got to go and shoot some aerials including of Slough House from the air,” explains Frost. “That set is just standing if you go to that street (Carthusian Street, EC1). It’s a real place.”

In episode five, there are a couple of tricky scenes which seem at polar opposites from a pacing and story point of view.

In the first, colleagues of Slough House are in one room discussing a course of action to find and rescue River. It’s a dialogue scene with quick fire barbs directed at each other. The second is a set-piece action scene involving a car crash on a London street.

“Regardless of whether it’s a big three-page dialogue scene or an action scene you’re looking for the same things. Where are the actors looking? If they look to a certain side of the screen that can cue you to cut to what they’re looking at. When do I need to see someone’s reaction? If someone does an eye roll can that help punctuate a line.

“The good thing about action scenes is you can go chronologically through it and just build it that way. Often with dialogue, I’ll hone in on a part of the scene where I know a performance is good and that a certain shot is going to be used. I’ll do that bit first then build it out from there.

“That particular scene in Slough House was tricky because it’s half a dozen characters standing in a circle, so you have to use the wides to establish where they are. There’s a lot of quick quips and comedy and it can be very easy to just bounce around everyone and risk feeling almost like a sitcom.”

The climactic action scene in episode five was originally planned as a single take and Frost was asked to come down to location for three nights and cut it whilst they were shooting.

“When I got there, it quickly became clear that that was not the best way to do the scene. There was so much that the audience needed to be able to read and understand that they decided to shoot it a different way.

“It’s quite an intense scene,” continues Frost. “Adam’s idea was to stay with the characters inside that car to retain the element of surprise and claustrophobia. We had all these cool angles including from GoPros on the front of the cars but we made the decision to stay inside the car.”

Frost had his laptop on a fold-up table and received records straight from the camera. “I took those very low-res QuickTime files, brought them straight into my Avid, and started to cut it that way, then presented a quick assembly for the director to view. This media has all of the time code information burnt in so that my assistant editor can later re-cut it with the actual rushes.”

Building a career in editing

“Once you’ve got that one thing on your CV, it becomes a little easier” Robert Frost, Editor

Frost has been interested in film and TV for as long as he can remember. As a nine year old he was making little animations with his friends. He studied Film and TV Production at York University and started out in the industry as a runner at Encore Post in London.

“They had suites for dry hire and one day an assistant editor invited all the runners in just have a look at how the Avid worked and what the editor did. I jumped at the opportunity. I went in with my notebook and wrote down as much as I could. Then a couple of weeks later, their trainee editor had to leave and I ended up getting the job.

“I think that’s because I’d shown that interest in making the notes but it wasn’t a ploy. I was just genuinely interested in it.”

His next step was as second assistant editor. “In this role, you’re mainly ingesting the rushes, making sure things are in sync, providing material for the editor when they need it. You move through your career at this point through recommendations. As you get towards the end of a job you put the word out about other jobs. Once you’ve got that one thing on your CV, it becomes a little easier.”

Frost’s own career made a leap forward when he began assisting editor David Webb, the managing director of editing house Final Cut. This included a couple of seasons assisting Webb on Netflix’ Sex Education, then Criminal: UK (also Netflix) before solo editing two episodes of acclaimed ITV drama Litvinenko (Webb cut the other two).

“As a second assistant you’ve got the benefit of being able to jump around from job to job but if you can settle down and work for one editor for an extended period you can show your skills and build a relationship.”

Frost still advocates the hands-on, ground-up route to the editor’s chair while acknowledging that opportunities are thinner on the ground then even a few years ago.

“Remote working is convenient and it means that people don’t have to commute into Soho every day or even need to be based in London but you do also miss the interaction and those chance encounters of the coffee in the kitchen and talking to people.

“It’s not like your dad has to be Steven Spielberg to get a job. You can meet people and being in a physical space is the better way to do that. I think the opportunities are still there so long as you’re interested in editing. If you’ve just done a degree then starting at the bottom of the ladder is still beneficial because you’re absorbing so much. Post facilities are full of people with all sorts of work and life experience and being around them is invaluable. Yes, there are fewer large drama shows being made but hopefully there’s still enough projects to go around.”

Frost himself has since completed the YA romantic thriller feature My Fault: London for Amazon Studios. With a fifth season of Slow Horses in the can, there are reports of a sixth season about to commence production.

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