Honestly, if you look back at 1995, British television was hitting this weird, experimental stride. You had Helen Mirren absolutely dominating as Jane Tennison, but then series 4 arrived and completely flipped the script. Literally. Instead of one long, grueling investigation spread over several weeks, we got three standalone films. It was a gamble.
The prime suspect season 4 cast had to carry a lot of weight because the format changed so drastically. Fans were used to the slow burn. Suddenly, they were getting these punchy, two-hour chunks. If the guest stars hadn't been top-tier, the whole thing probably would’ve tanked. But looking back now? It’s basically a "who’s who" of British talent before they became household names.
The Core Team Holding the Line
Before we get into the flashy guest stars, we have to talk about the regulars. Helen Mirren is, well, Mirren. By this point, she was Jane Tennison. In series 4, she finally hits that Superintendent rank, which changes the power dynamic in the room. She’s no longer just fighting the "old boys' club" from the bottom; she’s managing it. Sorta.
John Benfield returns as Michael Kernan, now a Detective Chief Superintendent. Their chemistry is always a bit prickly, but it’s the foundation of the show. You also see Richard Hawley as Richard Haskons. He’s the reliable heart of the team, the one guy who doesn’t seem to want to stab Tennison in the back every five minutes.
And then there's Jack Ellis as Tony Muddyman. If you watched series 1 or 2, you remember him as one of the chauvinistic thorns in Jane’s side. In series 4, particularly in the first film The Lost Child, he’s still that same aggressive copper. There’s a scene where he absolutely loses it on a suspect, and you realize the show hasn't softened its edges just because the format changed.
The Lost Child: A Masterclass in Tension
The first film of the season, The Lost Child, is probably the most famous of the three. It deals with a kidnapped toddler and a convicted pedophile who just got out of prison. It’s heavy stuff.
✨ Don't miss: Priyanka Chopra Latest Movies: Why Her 2026 Slate Is Riskier Than You Think
Robert Glenister plays Chris Hughes, the man everyone is convinced is guilty. Glenister is incredible here. He plays Hughes with this twitchy, nervous energy that makes you keep second-guessing him. Is he a monster or just a victim of a system that won't let him move on?
The supporting cast for this episode is equally stacked:
- Lesley Sharp plays Anne Sutherland, Hughes' partner. She’s caught in this impossible position of wanting to believe her man while fearing for her own daughters. Sharp is a legend for a reason; she does "internal conflict" better than almost anyone.
- Beatie Edney is Susan Covington, the distraught mother.
- Stuart Wilson enters the fray as Dr. Patrick Schofield. This was a big deal because he becomes a romantic interest for Tennison. It’s one of the few times we see Jane actually try to have a life outside the station, and Wilson plays the psychologist with a calm, intellectual charm that balances Mirren’s intensity.
Inner Circles and The Scent of Darkness
The second film, Inner Circles, takes Tennison out of her usual London element and drops her into a posh country club setting. It feels a bit like a "midsomer murder" gone wrong, but darker.
James Laurenson shows up as Paul Endicott, and we get a look at local government corruption. It’s a different vibe for the prime suspect season 4 cast, moving away from the gritty streets into wood-paneled rooms and golf courses. It’s not everyone’s favorite episode, but the acting remains top-notch.
Then we get The Scent of Darkness. This one is personal. It brings back the ghost of George Marlow from the very first season. Tim Woodward returns as Marlow, or at least, the shadow of him.
🔗 Read more: Why This Is How We Roll FGL Is Still The Song That Defines Modern Country
But the real standout in this third film? A young Marc Warren. He plays DC Andy Dyson. If you know Warren from Hustle or Van der Valk, seeing him here as a fresh-faced detective is a trip. He’s got that spark even then.
Oh, and keep your eyes peeled for Anthony Daniels—yes, C-3PO himself—playing a pathologist. It’s a "blink and you’ll miss it" moment that trivia nerds love.
Why This Cast Worked (When it Shouldn't Have)
The shift to the "film-of-the-week" format could have felt cheap. Like a procedural. But the prime suspect season 4 cast kept it grounded in the show's DNA.
The casting directors had this uncanny ability to find actors who could play "unlikable" but "human." Think about Christopher Fulford as DCI Tom Mitchell. He’s another one of those guys who makes you want to yell at the screen, but he feels real. He feels like a guy who’s been in the force too long and has lost his way.
Notable Guest Appearances You Might Have Missed:
- Kelly Reilly: Before she was Beth Dutton on Yellowstone, she was Polly Henry in The Lost Child. She was just a teenager then, but the talent was obvious.
- Sophie Stanton: She plays DS Christine Cromwell. She’s one of the few women on the squad who Jane actually seems to respect, providing a nice contrast to the usual hostility.
The Legacy of Series 4
Looking back from 2026, the way this season was cast set the template for modern prestige crime drama. You take a powerhouse lead and surround them with character actors who are capable of leading their own shows.
💡 You might also like: The Real Story Behind I Can Do Bad All by Myself: From Stage to Screen
It wasn't just about solving a crime. It was about how these people collided. When you watch Stuart Wilson and Helen Mirren together, you aren't just watching a detective and a shrink. You’re watching two people who are clearly too smart for their own good trying to find a middle ground.
If you’re revisiting the series, pay attention to the background players. Half the people who show up for three lines in a police briefing went on to lead major BBC or ITV dramas five years later.
How to Watch and What to Look For
If you’re diving back in, don't just focus on the mystery. Watch the power shifts.
- Watch the eyes: Mirren does more with a look in The Scent of Darkness than most actors do with a three-page monologue.
- Listen to the silence: Series 4 used silence effectively, especially in the scenes between Robert Glenister and Lesley Sharp.
- Spot the veterans: Check out David Ryall as Oscar Bream. He’s a veteran character actor who just brings so much weight to his scenes.
Basically, series 4 is a masterclass in ensemble acting. It proved that Jane Tennison didn't need a 6-hour arc to be compelling; she just needed the right people to push against. Whether it’s the heartbreaking vulnerability of the Sutherland family or the slick corruption of the country club set, the cast made the format change feel like a promotion rather than a shortcut.
Next time you’re scrolling through BritBox or your favorite streamer, give these three films a second look. They’re tighter and more experimental than they get credit for. And honestly, seeing a young Marc Warren and Kelly Reilly is worth the price of admission alone.
Go back and watch The Lost Child first. It’s the strongest of the trio and arguably contains some of Robert Glenister’s best work of the decade. Pay attention to how the show handles the ambiguity of his character—it’s a level of nuance you rarely see in modern procedurals that want to give you all the answers in the first twenty minutes.