Do you believe?
Critically acclaimed, Bafta Scotland award-winning paranormal drama Sea Of Souls is back for a third series this winter on BBC ONE and, once again, in attempting to explain the inexplicable, the team make viewers question the very world they've come to know...
It's a welcome return to Clyde University's Parapsychology Department where the dedicated team – Dr Douglas Monaghan (Bill Paterson) and his two researchers Justine McManus (Dawn Steele) and Craig Stevenson (Iain Robertson) – are, once again, drawn into a world of the strange and the supernatural, investigating deathly séances, powerful premonitions, vivid night terrors, sinister hauntings, demonic forces and macabre black magic.
Over six individual one-hour stories, Sea Of Souls confronts the dark, unanswered questions which surround us all. Events that some find terrifying, the Sea Of Souls team find compelling and fascinating.
The third series opens with Monaghan confronting his own past after a séance to contact a dead child goes horribly wrong. The team believe the child's father could be possessed by an evil spirit, but the truth is even more chilling and unpredictable than they could ever have expected.
Meanwhile, one year on, Justine and Craig are more united, working closely together even when the most obscure and sinister events occur.
Newly qualified Justine realises her own psychic abilities are much more powerful than she could have ever imagined and when Craig, the sceptic, discovers her secret, he is forced to question the very essence of his dearly-held beliefs.
Head of Drama for BBC Scotland and Sea Of Souls Executive Producer, Barbara McKissack, says: "In this series we learn a bit more about the characters and explore their lives, as well as the cases they are working on.
"There are some quite personal stories about the team throughout the new episodes that have the potential to turn their worlds upside down. We see the regulars being personally and professionally challenged and much more uncertain about what's real and what's not."
She continues: "I want viewers to be really scared by these new episodes. I'd like them to have fun watching this series, but when each hour is over I want them to be too jumpy to go and make that cup of tea."
The show's producer, Stephen Garwood, agrees: "This year we've aimed to make the audience feel even more scared, so each story should feel like a rollercoaster ride. The trick is to be able to provide the shocks and bangs, but not where people expect them to be.
"This show has everything, the thrills and spills, the action, an outstanding cast and fantastic Scottish locations - all the high calibre storytelling ingredients you need."
Regardless of whether you're a believer, a sceptic or a doubter, for many of us there is something strangely fascinating about the paranormal - which explains why Sea Of Souls has been sold to over 40 countries worldwide including Russia, Saudi Arabia and Kuwait.
Garwood says: "It touches upon every aspect of the paranormal and viewers can tune in not knowing what they're going to get.
"For me as a storyteller, I find this subject endlessly fascinating as it's very much about stories that happen to ordinary people.
"Apparently, more people in the UK believe in the paranormal than they do in religion, so what we have tried to do is look at the ordinary and everyday juxtaposed against the supernatural. We take our story and put it through the Sea Of Souls filter."
Supernatural phenomena which cannot be explained by conventional science appears to have the potential to capture our collective imaginations - and according to McKissack, that will be made even easier by the third series' new format of six one-hour episodes.
She explains: "It's a much better, faster paced format for this kind of show. Sea Of Souls is top notch Thriller TV."
Guest stars include Dragon's Den entrepreneur Duncan Bannatyne, Frances Grey, Phyllis Logan, Ronald Pickup, Rae Hendrie and Clare Grogan.
And the series finale ends in suitably dramatic fashion with a guest appearance from the eighth Dr Who and star of Hornblower and Kidnapped, Paul McGann, who plays a charismatic, yet sinister, businessman embroiled in black magic.
"We are thrilled to have Paul McGann on board as a guest artist," says McKissack.
"He is a real treat to work with - he's interesting because he's one of those performers who can be quite a sexy presence on screen one minute and then very scary the next. Which is the perfect combination for an unsettling show like Sea Of Souls.
"What I think is fantastic about Sea Of Souls this year is that it's truly Glaswegian. Our three stars are Glaswegian, the majority of the cases they deal with are all rooted in the city and we see a lot of Glasgow itself - which is such a beautiful location to film in."
Created by David Kane, Sea Of Souls is a BBC Scotland Production.