Arctic Circle (aka Ivalo) is set in the unforgiving polar region, amidst the icy landscapes of Finnish Lapland. After Nina Kautsalo, a Finnish police officer, finds a dying prostitute in an old cabin in the wilderness, the ensuing criminal investigation takes a surprise twist when a deadly virus is discovered in the prostitute's blood. However, when Thomas Lorenz, a German virologist, travels to Lapland to investigate the virus, he and Nina suddenly find themselves in the middle of an exceedingly unusual criminal investigation.