Under Salt Marsh’s Rafe Spall talks impact of nepotism in his career: "That’s called an advantage"

What’s the view from your sofa?

It’s an open-plan TV area that has the TV, obviously, and a record player with lots of records beside it. And lots of baby toys, because we have an 18-month-old.

You have four children. Do you enjoy being a dad?

Being a father is my proudest achievement. My kids are 14, 13, 10 and 18 months, which is quite a big stretch, and sometimes the sense of responsibility is pretty crushing. But it’s what sustains me; it’s what keeps me going. It’s really defined by what you get wrong. I get a lot wrong and I find it difficult sometimes, but I show up and I try. Looking after these kids and giving them as nice a life as I can is really the only thing of any worth I’ve ever done.

Eric Bull, your character in Under Salt Marsh, has entered the pantheon of British detectives. Tell us about him.

He’s awkward. Brusque. Into mushrooms. He’s a gay man – or a man who happens to be gay. A lot of that stuff was on the page, but I had free rein to decide where he was from because he needed to be not from there, not Welsh, so I decided to go West Midlands. My partner [and Trying co-star] Esther Smith is from Stourbridge, and I like the idea of the Black Country. It’s geographically close to north Wales and you don’t hear the accent much on television.

Given that Bull’s been conducting his murder investigation under the threat of an almighty, evidence-destroying storm that finally hits this week, how was filming Under Salt Marsh?

It was one of the most difficult pieces of shooting I’ve ever done. Given that the show is, essentially, about a storm, it meant being under rain machines from November through to March in north Wales and Cardiff – and that’s physically quite demanding. There were a lot of wetsuits involved. But we’re well paid, and it beats digging a hole in the road.

Trying, your Apple TV sitcom that’s now being shown on BBC One, must be a cakewalk, comparatively?

When I go home after a day of Trying, I’m much more exhausted than I would be after a day under a rain machine on Under Salt Marsh. There are three jokes on every page that need to be squeezed for every bit of juice while looking effortlessly like you’re not serving up gags – and that’s mentally taxing. It’s one of the great merits of the show that it mixes comedy capers and set pieces with real emotions. And it is also really joyful because I’m with my partner and people I’ve made it with for six years. I draw on a lot of myself for Jason so he’s quite different from Bull.

Did you always want to be an actor?

For as long as I can remember, but I had an amazing role model…

You refer, of course, to your dad, actor Timothy Spall. So let’s talk about nepotism.

People get insecure talking about nepotism because they think that it makes them look bad, but you’ve got to be real. My dad being a famous actor definitely meant that a casting director would look at a list of potential young actors and would want to see what Timothy’s son is like, out of interest.

That’s called an advantage, and compared to Esther or Kelly [Reilly, his Under Salt Marsh co-star], who didn’t have a leg-up, it’s an unfair one. Now, in my experience, it gets you through the door, but it doesn’t get you the job. Why would a film-maker who has spent years trying to get a film off the ground put someone in it that he or she didn’t think was going to be good?

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