So a Finnish boy and a Finnish girl meet in a noisy night club and leave together. As they get outside, he says: “Your place or mine?” And she says: “Why are you talking so much?”

I had this typical Finnish joke in mind a lot while watching Tellus (2014), a TV series from Jukka-Pekka Siili about a bunch of Helsinki eco-terrorists and the security squad dedicated to taking them down. Starting out as pamphleteers, bloggers and monkey-wrenchers, the Tellus protestors become increasingly more pro-active, until a fateful day when arson on an industrial estate leads to the death of a security guard. This takes them out of the realm of misdemeanours into serious felony, and puts seasoned detective Taneli Lokka (Pirkka-Pekka Petelius) on their trail.

The Tellus group is a stereotypical coven of urban guerrillas, with some more militant than others, but each self-righteously assured of their nobility of purpose. Notably, they are always shown drinking a variety of beers, to ensure that no single brand can be associated with terrorism. Someone had a meeting about that, I bet. True tension mounts when their nominal leader, Eeva (Minkka Kuustonen) is targeted by an undercover police informant, Alex (Lauri Tilkanen). He’s under orders to get closer to the organisation’s heart, but this inevitably brings him into moral conflict, not only over his own feelings for Eeva, but his attitude towards the group’s crimes.

The romance between the leads is oddly paced and posed, as if two emotionless puppets are going through the motions of dating… or perhaps as if two players believe each is duping the other. She resists his advances coldly and dispassionately, only to suddenly agree to a date with equal indifference, so the pair of them can bike around Helsinki like a couple of smug hipsters. Even then, Eeva presents every hallmark of being a self-involved, self-regarding dullard, less of a love interest than a love disinterest. Alex, meanwhile, is hardly a catch himself, so cocky that he practically brow-beats her into a snowbound picnic, despite very obvious signs that she barely notices him. And then suddenly they are all smiles and touchy-feely. Apparently, a relationship has broken out, like hives. One wonders to what extent this is a deliberate evocation of her single-minded vocation and his clandestine mission, and to what extent it’s just because they’re a couple of joyless Finns. Maybe there is some witty, subtle nuance of Finnish social interaction that I am missing. Or maybe the way to pick up Finnish girls really is to bombard them with phone calls until they relent.

But there is a lot of double-bluffing going on in the script. A scene which first appears to be a hackneyed pixie-dreamgirl moment, of Eeva lying on her back staring at the sky, is revealed to be a scouting mission for another attack – she is not laying low on a hilltop as a poseur, but because she doesn’t want to be seen. The story comes alive, explosively and unexpectedly, in a throwaway kitchen scene wherein the stressed investigator Taneli suddenly turns on his listless teenage son for wasting food. It’s a dinner-table sequence that many writers would use as expository filler, but actor Petelius lets loose in an incandescent rant, tying up family tensions, workplace stress, and a startling revelation – that deep-down he is sympathetic with the eco-terrorists’ beliefs.

This pivotal moment cleverly repositions all arguments about Them and Us. We really are all in this together. Taneli and Alex and Eeva and her hardcore friends are all in total agreement that Something Must Be Done. They simply disagree on the methods, in a drama that focuses itself very much through an ecological lens, both in terms of the troubles that the Earth is facing, and a thought experiment as to the attitude and appearance of Green extremism.

Jonathan Clements is the author of An Armchair Traveller’s History of Finland.