You could call I Still See You a supernatural thriller, or just a straightforward ghost story, because it's certainly both. What it is not, many of you will be relieved to hear, is a graphic horror film. It goes deeper than that.

In the new young adult directed movie, Dermot Mulroney (who plays school teacher and confidant August Bittner) lives in a town where an unexplained supernatural event has killed thousands, but they somehow still linger on as ghosts.

These ghosts appear and disappear throughout the day, startling the living, turning up in the places that were once important to them. But we discover they're just echoes, momentary apparitions that quickly vanish like smoke or fog.

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First we meet troubled teen Veronica Calder (played by Bella Thorne) who has lost her father in the event, or rather mostly lost him. Because it turns out although he passed he still shows up at the dinner table from time to time to wordlessly read his morning paper.

Bella Thorne in I Still See You

Bella Thorne in I Still See You

Veronica is worried that more and more ghosts seem to be appearing around town since the event and she's worried what that might mean for her little Illinois neighborhood. But who to tell? The first clear indication we get that her high school teacher August Bittner (Mulroney) isn't on the up and up comes when we see his house for the first time.

It's the kind of high tech pad you'd imagine Tim Cook living in, not some low-wage science professor who teaches public education. In a world where the dead never rest in peace, nothing is ever what it seems.

I Still See You has an undeniably 80's teen supernatural thriller vibe, and I mean that in a good way. Mulroney, 54, agrees. “Yes I think you could call it a supernatural thriller, but it's really also a ghost story,” he tells the Irish Voice. “All of these aspects are well combined in this movie. There's also the whole backstory with this huge nuclear fusion science experiment laboratory that goes wrong. I just love that part.”

At heart, the question asked by I Still See You is the stuff of classic myth: just how much are you willing to give up in order to get something? “Absolutely,” says Mulroney. “It a question that plays large in this movie. I have high hopes that a young audience will really really get that its broader in that way.”

Mulroney's character's palatial home on a high school teacher salary makes him instantly suspicious though. Which means that as well as being a ghost story I Still See You turns into a police procedural for a while, too. “It definitely has all the elements of a fun film,” he says.

Of course, I have to ask him about Dylan McDermott, the other Irish actor he gets frequently confused with, and vice versa. “I mean our surnames look broadly similar to some people,” he laughs. “We always been kind of in a parallel Irish American universe. Finally we got to reach across the divide recently and became good buddies when we finally worked together on a sitcom over here called L.A. to Vegas. For the first time we were seen in the same room together.”

Dermot Mulroney and Dylan McDermott finally meet

Dermot Mulroney and Dylan McDermott finally meet

What was it like to be called Dermot Mulroney growing up in Virginia? “It was a time when so many kids were named and Paul and Scott. Those were the American names around. And of course still Bill and Bob. Nobody had names like us (his sister is named Moira, and his three brothers are called Conor, Kieran and Sean). I'm not sure why we got those names, because we weren't new immigrants. Our parents and theirs go way back in America. For some reason they gave us traditional Irish names.”

Has he been to Ireland? “Only once in 1989. And it was a beautiful trip I'll never forget. I came to Dublin then went up the west coast through your neighborhood in Donegal, and I had the international trip of a lifetime.”

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His family have maintained a strange connection to Ireland, he says. “My aunt Sarah recently had her DNA ancestry test and she's 93 percent Irish, man. That's hard to do over here after years of immigration. That's impressive actually. We're holding strong. Everyone should know we're holding strong,” he laughs.

And what does he want people to know about I Still see You? “I think it's going to be the most interesting supernatural thriller of the fall, of all the supernatural movie releases that are coming out. I watched this movie with the 13-year-old son of a friend of mine and he fell for everything and couldn't wait to tell his friends. So I think it's a little hit in the making.”

I Still See You opens Friday, October 12.

Dermot Mulroney stars in I Still See YouLionsgate Films