It all begins with Kalmann in hot water. He's at the FBI Headquarters in Washington, arrested during the Jan 6, 2021 riots at the Capitol Building. All he wanted was to visit his American father in the US for the Christmas holidays - but his dad takes him (and a group of MAGA friends) to the protests in Washington to "regain the house which is ours". He is promptly arrested during the riots. Thanks to sympathetic FBI agent Dakota Leen, he's soon on a plane back to Iceland. But not before Dakota informs him that his recently deceased grandfather was on an FBI list of suspected Russian spies working in Iceland during the Cold War. Back home, Kalmann begins to suspect that his grandfather's death from "heart failure" was a murder. His maverick investigation uncovers another assassination and takes him to the site of a US radar station abandoned in the 1970s. So, there are now two deaths to be solved and the threat of more to come. Much to do for our unlikely amateur detective who somehow never loses heart.