SAMUEL Barnett was pleasantly shocked when he walked on stage at San Diego Comic Con last summer. The British actor was at the world’s largest fan convention promoting his new series, Dirk Gently’s Holistic Detective Agency, in which he stars as the eponymous odd-ball sleuth.

“Douglas Adams’ Dirk Gently novels are well known in the UK, but perhaps not the same extent in America,” he recalls.

“But because of that, the people in the US who are fans tend to be super-fans. The room was full for our panel. It was the same at New York Comic Con. We showed the first episode at the Madison Square Garden screening room, which has a capacity of 5,000. It was packed.”

Though the late Adams is best known for his Hitchhiker’s Guide to the Galaxy series, devotees of the English writer rate the Dirk Gently books just as highly. The titular detective is a magical realistic Sherlock Holmes, whose unique selling point is that he uses “the fundamental interconnectedness of all thing” to solve a crime “in its entirety”.

Both the novels and the TV drama exploit the eccentric premise to the full. When we meet Dirk in the new series, which has just debuted on Netflix, a murder has been committed and Gently takes it upon himself to solve the crime, with the aid of hapless sidekick Todd (Lord of the Ring’s Elijah Wood).

Cue screw-ball adventures, zany misunderstandings and more whimsical banter than a Monty Python boxset. If you’re in the mood for high concept wackiness it’s the perfect pre-Christmas romp — one that will engage your grey matter as surely as it pushes your humour buttons.

“The way television is being made now, people are okay if there is a lot to take in,” says Barnett. “It is quite complicated, but that’s a good thing as it keeps you on the hook, I think.”

Dirk Gently — not to be confused with a 2010 adaptation starring Stephen Mangan — was screened over the autumn on BBC America. It now reaches Europe courtesy of Netflix. Because of the dense plot, bingeing might be the perfect way to watch, says Barnett. “You’re not having to dumb anything down because you know the audience will make the effort to keep up,” he says.

“Personally I love binge watching. I rarely wait for something week by week. I want to get straight to the next episode. I think Dirk Gently will benefit from such an approach.”

Barnett was born in 1980 in Whitby in Yorkshire. He will be best known to audience as vampire Renfield in the cancelled gothic fandango Penny Dreadful, filmed in Dublin.

“I was devastated when they canceled Penny Dreadful,” he says. “Whether or not I was going to be in the next series, I absolutely adored it. I had the best time in Dublin. And to play a vampire was amazing because Bram Stoker wrote Dracula in the town where I grew up. So it meant an awful lot to me.”

Though Penny Dreadful raised his profile somewhat it was a nonetheless a new experience to play the lead in a major new series. Fans have been graceful he says. And when they haven’t, they generally make their criticisms behind his back.

“People have been very kind… even on Twitter,” he laughs. “Twitter is an interesting place. Sometimes you think, ‘If we were in a room would you say what you are saying to me here?’. But generally they have been extremely generous.

“The thing is, when people don’t like it they generally don’t include your Twitter handle. A few people have let me know just how much that hate it. But that’s fine. It just goes to show that we haven’t created something bland and meaningless.”