David Tennant has said he thought the idea of playing his Broadchurch character again in the US remake Gracepoint was too unique to turn down.

The actor played police investigator Alec Hardy in Broadchurch and has swapped to US character Emmett Carver for Gracepoint, the only actor from the ITV series to recreate their role.

Asked at the TCA event in Los Angeles if acting the same story again was strange, he said: “That was part of the reason it felt like too extraordinary an opportunity to miss. It felt like a really unprecedented thing to be asked to do.

“It doesn’t really feel surreal. It perhaps seems like an odder notion than it ultimately is. Acting’s often about repeating the same part of a story again and again – you do a theatre show, you tell the same story eight times a week with the same actors surrounding you, so there were enough variables to make it fresh and challenging.”

He continued: “You know this is a story that works and that any differences are going to be curated by producers that you know and trust.

“There’s not going to be a pilot, there’s not the torture of all that, it’s not 20 million episodes… There are too many things that are right about this to let this opportunity go by. Then you think, ‘I can’t tune in next year and see some other person doing it’.”

On changing to a US accent, he said: “In a way that was useful because it gave me a new point of concentration to work from and having a different voice makes you a different person. It makes you move differently, it makes you think at a different rate, it makes you approach things differently.

“I like working in accents, I like the sense of transformation it gives you. I like when the character doesn’t feel like me, so anything that helps me to get there, I enjoy.”

David has switched co-stars from Olivia Colman to Anna Gunn, but said he couldn’t pick favourites between the US and UK cast: “I love deeply everyone from the original cast, but equally I love everyone from the new one, so it would feel wrong to not want all these people to be playing all these parts.”

He refused to spill details of the plot for the second series of Broadchurch: “No I can’t, I’d get shot in the head.”