Bjorn Ironside has invaded Canada.  Cameras are officially set to start rolling on Season 4 of Vikings in Ireland this spring, but the Canadian co-production is getting a head start in northern Ontario.

History Canada has confirmed that Alexander Ludwig—who portrays Ragnar Lothbrok’s eldest son on the network’s Thursday night drama—is in Sault Ste. Marie, Ont., working on preproduction for Season 4 prior to initial production starting on the Emerald Isle. History didn’t release any details as to the storyline surrounding Ludwig being in Ontario.

On Friday, the city’s mayor, Christian Provenzano, posted a picture via his Twitter feed, welcoming the Vancouver native to the area.

Last Thursday, Ludwig tweeted his location to followers and posted a picture on his Instagram account showing him arriving in the outpost.

Vikings airs Thursdays at 10 p.m. ET/PT on History.

The advances in visual effects in television has made it difficult to tell what’s real and what isn’t, especially on a program like Vikings. That’s where the folks at Mr. X and Take 5 come in. The production houses are charged with creating everything in History’s Thursday night drama, from Ragnar Lothbrok’s longboats to King Ecbert’s expansive compound to the soaring peaks surrounding Kattegat.

That work falls to Mr. X Inc. and Take 5 Productions, two studios specializing in visual effects and animation for television and feature film.

“We get scripts later in the process than the producers and the directors,” Dominic Remane, visual effects supervisor at Mr. X, says. “We’ll make a note of an establishing shot of Kattegat that has to start high and wide, or a fleet of 60 longboats leaving Kattegat for Wessex.” From directions in the script, Remane and his team of 60 know they’ll have to add in more of Ragnar’s ominous ships—only a handful of real longboats exist—and that the end of the real lake the boats are on needs to be deleted and elongated to look like a Scandinavian fjord.

Bill Halliday, visual effects producer at Take 5, says both companies see Vikings as a project with the hallmarks of a feature film look hemmed in by the constraints of a television show budget. And, as Halliday points out, Vikings regularly surpasses movies when it comes to the number of visual effects done in one episode.

“In the first episode of Season 3 there were over 100 visual effects, which by television standards is a huge amount,” Halliday explains. “In Episode 8, the invasion of Paris, there are over 300 visual effects which is remarkable. I worked on The Tudors and we did fewer effects in a season than we would on one episode of Vikings. A feature film runs around 200 visual effects.” It’s a stunning scope, Halliday explains, and one that—if everyone has done their jobs right—nobody notices.

A difficult aspect of the job with regard to Vikings is meeting the demand of show creator Michael Hirst, whose imagination pushes everyone to be creative. There have been times when they couldn’t deliver; Halliday notes a recent request to create a fully-digital animal to interact with a character couldn’t be created within the short time frame TV works in.

Perhaps the biggest jewel of Vikings’ Season 3 crown will be Ragnar’s invasion of Paris. It’s a story angle that’s been ramping up all season and cast member Clive Standen told me it will blow viewers’ minds. Remane worked closely with the show’s production designer, Mark Geraghty, to research the oldest castles in Europe to base Ragnar’s 850 AD attack on. They found it in Carcassonne, France, where surveying was done to select parts for which they could base Paris of the time period on.

“I’ve always wanted to be working in visual effects, but I never thought I’d be doing it to this level,” Remane admits. “I never thought I’d be going to Europe, France and Ireland, going to Norway and filming plates for the show.”

Vikings airs Thursdays at 10 p.m. ET/PT on History.

Ken Girotti has directed some of the most critically acclaimed—and entertaining—television shows in recent years. In the U.S., he’s worked on Denis Leary’s firefighter drama Rescue Me, Dick Wolf’s Law & Order: Criminal Intent and spy drama Covert Affairs.

In Canada, the homegrown man behind the lens has worked on Combat Hospital, Flashpoint, the Stargate franchise, ReGenesis, Copper, Bomb Girls, Orphan Black and Saving Hope.

Girotti’s work can currently be seen on History’s sweeping Vikings, tracking the ongoing adventures of Ragnar Lothbrok and his followers as they explore the ancient world, and includes an attack on Paris later this season. We spoke the veteran director about the challenges and rewards of working on a series like Vikings, which involves filming longboats on rough seas and choreographing intense battle scenes for the small screen.

Vikings is a really cinematic series that deserves to be on a feature film screen.
Ken Girotti: I have to agree with you. The scope and scale of the show looks pretty good up there.

Are you the type of director who can just watch you work afterwards and enjoy it, or are you picking things apart?
Oh no, I play director. It never stops with me. It’s either, ‘Wow, that worked out really well,’ or ‘Oh my god, how could they have done that?’ or a mixture of those things. That’s part of the deal when you’re in television.

When you get a script from Vikings creator Michael Hirst, what is the first thing that you do? Walk me through the process.
The first thing I do is sit back and have a good read and see how it all washes over me. Almost always with any script—whether it’s from Michael Hirst or anyone—you’ll have questions about what exactly some things mean. And sometimes you never ask those questions because you want them to remain questions. Then I take a second read and try to fine-tune the script and put it through a filter. Are things clear? I’m starting to circle a place where I see the story unfold in my mind in pictures and words. That’s when the real job of directing begins because I start to interpret what Michael has written for me and try to embellish it and move it forward.

Directing is such a collaborative process. You have your vision and you’re getting into someone else’s sandbox. Is that sometimes a challenge?
On something like Vikings it’s pretty easy because I share a sensibility with Michael. I feel like we have a commonality in the way that we approach life and truth, beauty and art and all of those things. I have a deep respect for his writing; he writes in such an evocative way that speaks to me personally. There are some things that I become completely obsessed with. One little line.

One of the things that I never really observed about Vikings before is the exploration into religion.
I think it’s very subversive. It’s never on the surface. There’s slashing with axes and stuff, but everything that they do has an effect on the next thing that they do. And that’s very existential, I think.

Filming those longboats must be a challenge.
They are the most difficult things to manage ever. They’re difficult and annoying and beautiful all at once. You think about moving a camera while moving an actor on dry land and camera goes this way and the actor goes that way in a nice little coordination of movement. Then you add an element where you can’t predict where anything is going to go and that’s water. It creates organizational anarchy. The marine guys are amazing and my first AD, Raymond Kirk, is truly an amazing first AD. They had to build docks for these boats. They hoist them in with cranes. It’s immense and the logistical challenges with regard to the boats is just huge.

The battle scenes are intricate work too. I’m thinking of that battle in Episode 1 of this season.
We were on that site for six days, I think. It was a pretty big sequence. What we tried to show there was sort of a storming the beaches at D-Day. There was something similar earlier in the series where Jarl Borg rolls up on Kattegat. This was quite a bit bigger and we tried to stay on the beach for as long as we could and we wanted to show how hard it was to get your feet out of the water as a Viking and fight against those Mercians.

I can’t imagine what it would have been like to be a Mercian and see these big, ugly, hairy guys with axes on boats rowing towards you. It must have been horrible.

Vikings airs Thursdays at 10 p.m. ET/PT on History.

(Image credit: G. Pimentel)