What was the concept for the trolls, and how did you arrive at it?
Martin Andersson: When you're working with something this dear to an entire people you have to tread lightly. You are not really in a position to make any design that goes against the classic trolls we are all used to. If you've been a tourist in Norway you have probably been bombarded with trolls.
Of course you can say that no one knows what trolls look like anyway so you have some freedom, but it's limited. Imagine how pissed off people would be if you made a serious movie about ancient Rome and dressed them all up in pink ballerina costumes...
The design of the trolls was really a back and forth thing between the director, supervisors, our concept artist (Nikolai Lockertsen) and myself. Niko drew several designs during the creation process. I did the roughs in ZBrush based on maquettes Filmkameratene provided and Nikko’s drawings, but in the end the final design didn't end up like any of the concepts. It's close to the concepts, but the director didn't really know what he wanted. For reference I used anorectic boys and girls. Also photos of people who had been stabbed, blinded, attacked with acid and a lot of other references I don’t ever want to see again or talk about for the Tusseladd (Tosserlad). Fat Russian wrestlers were the main photographic source for the Dovregubbe (Mountain King). Quite a contrast! You get kind of immune after a while looking at the pictures, but the rest of the studio went "ewww, you sick, sick man" a couple times a day when walking by my screen which always had the photos open. The balance between fairy tale and realistic monster was also sensitive. We didn't want it to be a generic monster that could be any kind of monster but we also wanted it to be believable on-screen. When I needed I could also arrange sit-downs with our VFX supervisor (Colin Doncaster from Peregrine VFX) and Animation Supervisor (Jamie McCarter). They were usually available for discussions and sometimes sit downs were an extension of the dailies. Those sit downs where we drew on some prints and discussed shapes, muscles and what-not were extremely valuable. I'm glad I had a chance to work with them.
Which creatures were you involved with for the project?
Martin Andersson: Storm Studios did two trolls for this movie. The Tusseladd is a 7-8 meter tall, three headed skinny troll and the Dovregubbe is a 3 meter tall fat one. The Tusseladd works alone while the Dovregubbe trolls are found in larger groups. In the forest, you can run but when you're stuck in a cave with a group of Dovregubbe trolls you're in for an experience to tell your grandchildren. If you get out of there alive, that is.