The Hitman's Guide to Housecleaning is a novel by Hallgrímur Helgason. His first novel to be composed in English, it was actually first published in Icelandic, in the author's own translation, as 10 ráð til að hætta að drepa fólk og byrja að vaska upp. It has also been translated into Dutch, German, Czech, Russian, Polish, Danish, and Italian.
The novel takes place from May 15 2006 to May 12 2007. Tomislav Bokšić, nicknamed Toxic, after fighting on the Croatian side in the Croatian War of Independence, has moved to New York City and become a hitman for the Croatian mafia. His 67th victim is an undercover policeman and he has to flee the country. At the airport, he avoids detection by murdering a priest and takes his identity. Toxic uses the priest's boarding pass to Reykjavík.
Toxic is met by two small-time Icelandic televangelists, Guðmundur and his wife Sigríður. He passes for Reverend Friendly until the police come looking for him. He flees and seeks refuge with his hosts' daughter Gunnhildur, who dislikes her parents' religiosity and is pleased to harbour a criminal. Toxic hides in her attic, begins to reflect on his life of violence and the two begin a relationship.
Toxic discovers that his girlfriend in New York City, Munita, has been brutally murdered. He attempts to kill himself by throwing himself off a bridge. Surviving, he makes his way to Guðmundur and Sigríður's house, where he begs forgiveness and assistance. The two decide to take him in, wrap him in bandages, and get their friend Þorður, a preacher, to purge Toxic's soul through a programme of bodily mortification and spiritual reflection. Guðmundur uses his underworld and political connections to get Toxic an Icelandic identity as Tómas Leifur Ólafsson, a job, and a room in an illegal boarding-house for East European immigrant workers. Toxic's relationship with Gunnhildur develops. Discovering that some of his Lithuanian neighbours are gangsters, he steals a pistol owned by one and moves out to Gunnhildur's house. He settles into Icelandic life, keeping the pistol hidden in his shoe sole.
While watching the Eurovision Song Contest 2007 with Gunnhildur, her parents and their friends, Toxic (now Tómas) receives a visit from his old mafia colleagues Niko and Radovan. They drive him to the lava-fields of the Reykjanes Peninsula to kill him. Toxic disables them, leaves them alive, and drives back, injured, to the party. The novel ends with him falling through the front door, and discovering that Serbia has won.