In the dense forests of Finland, a hulking creature with glowing red skin crawls out of the earth and races towards parliament.

The monster hijacks a limousine containing Finland’s top ministers - who have abruptly stopped drinking cocktails and throwing fistfuls of cash over their female escorts - and drives them half-insane with remorse and fear.

This is no Hollywood horror film, but a scene in the latest political advert from the Finns Party, the nationalist, anti-EU group that has lit a firecracker under Finland’s usually docile political scene.

Finland is supposedly the happiest nation in the world - at least according to several surveys - with a coveted welfare system, globally renowned schools, stunning lakes and a sauna in every second home.

But in this month’s European elections, one recent poll suggests the Finns, with their fierce rhetoric against mass migration and Brussels rule, are set to become the country’s most popular party.

Sitting in Finland’s parliament building, a giant neo-classical structure with imposing stone steps built in 1926, the Finns’ deputy chairman Laura Huhtasaari suddenly becomes animated when asked why she is so angry about the state of politics.

“It’s all about greed, power and money. Finland and the EU is weak on crime, weak on borders, weak on protecting nation states. They [mainstream politicians] just let this happen and it’s terrible... I want my country back.”