It's not that the 63-year-old actor is worried about whether the series does well, but because the subject matter is rather contentious. After all, it's not every day that he plays an exorcist priest who must lead a battle between good and evil, fighting satanic conspiracies on every side.
"We're tackling issues head on in this," Martin explains.
"When we're talking about controversy and the Catholic Church - you wait! Just wait till we get to the last two episodes! There is some pretty shocking stuff. As far as the demons are concerned, it's nothing less than the end of all things.
"It gets big - there's some quite shocking things coming up. I'm ready for the complaints, absolutely."
But does he think the number of complaints will end up being the focus of the programme rather than the actual content?
"I'm sure it will shock people, but you have to take risks," Martin says.
"I really truly think the majority of people don't want more of the same. When Judge John Deed first went out I got more correspondence about that than anything else I've ever done in over 40 years. Most of it was thanking us for doing something different. And there were quite a few shocking things in that."
Playing Father Jacob is something of a departure from Martin's previous roles - viewers will remember him as student Robert Croft in Coronation Street and undercover detective Ray Doyle in The Professionals.
"There was a mixture of things, which made me interested in the idea of playing an exorcist," he says.
"I've been in the business for 45 years, which gives me an insight into what's missing, and I thought what was missing was simply something different, something new, something we hadn't seen before. Everything that's out there at the moment is kind of the same, or related to each other in some way - it's all medicine, or law, or cops. And it all has an underlying sense of negativity."
Martin's aware though that Apparitions may not be to everyone's taste.
"Of course it's dangerous, in terms of possibly upsetting people - we're taking a risk," he says.
"I would bet a fortune that the vast majority of people will be fine with it. And there will probably be a small minority who aren't fine with it, as there always is when something different, thought provoking and challenging comes on the screen.
"I suppose a warning before the programme starts wouldn't hurt, to say some viewers might find some scenes difficult. I wouldn't have an objection to it, and given the subject matter it may be a good idea."
Religious subjects are known to court controversy - even the Harry Potter films saw a backlash from right-wing Christian groups - but Martin is prepared for trouble.
"I don't know what the Church will think about it. There will be some people on the extreme right of the Catholic Church and there will be liberal Catholics who say there's no such thing as demons," he says.
Priests were available on set throughout filming, and Martin says that one in particular, Father Dave, was extremely helpful.
"I went to him to say if there's anything that makes you uncomfortable, let me know and we'll see if we can do something about it," says.
"The only discomfort for Father Dave was in episode four where we filmed in an abortion clinic. He was profoundly uncomfortable and distressed. He couldn't bear being in this place where, in his point of view, murder was carried out 20 times a day. But other than that, they loved it! Father Dave loved the all the blood and gory bits!"
Films or TV shows dealing with exorcism are often plagued by unexpected events, but Martin says the Apparitions set was trouble-free.
"I wasn't affected in the slightest during filming," he says.
"I know traditionally films about exorcism have had some sort of curse. Without wanting to sound too pious, this has felt like it's been blessed! Everything's gone right and the whole experience has joyous. We've even had one or two little miracles."
Even so, he admits that he did have his own little form of protection on set.
"Two days before we started filming, I received in the post an envelope from the Missionaries of Charity, Mother Teresa's charity," he explains.
"It was a little wooden rosary, a gift inviting us to donate. I found the timing very strange, I'd never heard of them or from them before, so I carried that little wooden rosary with me all the way through filming."
Martin may not have experienced anything out of the ordinary on set, another actor did.
"Shaun Dooley, who plays Liam in episode one, is the most pragmatic and sceptical of all of us. But he was in the shower at the hotel in Liverpool and he came out all ready to go to work, went back into the shower room and water had flowed into a perfect cross on the floor! We weren't very impressed, but then he showed us a photo on a mobile phone. It was a perfect cross in every respect - you could have measured it."
EXORCISM IN POPULAR CULTURE
The Exorcist: The 1973 film has been voted as one of the most scary films of all time.
Repossessed: This 1990 movie, which starred Leslie Nielson, was more comedy than horror.
Grudge 2: A British production, released in 2006, which was based on a Japanese series
1920: In 2008 Bollywood decided to get in on the action and produced a film based on exorcism.
The Exorcism Of Emily Rose: Based on the true story of Anneliese Michel, this scary flick had people hiding behind their popcorn when it hit cinemas in 2005.
Apparitions starts on BBC One on Thursday November 13.