Skurken i muminhuset (Literally: The Villain in the Moominhouse, commonly referred to in English as An Unwanted Guest) is the thirteenth in the series of Tove Jansson's Moomin books and the fourth and final picture book, published in 1980. The book was never translated to English. The story follows Little My and Moomintroll as they trail a mysterious intruder in the Moominhouse.
An Unwanted Guest is notable in that it features a very large cast of characters from almost every book, who are all shown to be living in the Moominhouse, like Grandpa Grumble, The Astronomer from Comet in Moominland, Toffle and Miffle, Toft, Snorkmaiden, Misabel, Sniff and Stinky.
Instead of the usual drawings by Jansson, this book is illustrated with photos taken by her brother, photographer Per Olov Jansson. The photos show the rooms of the Moomin House model, now on display in the Moomin Museum.
It is one of only two Moomin books to never be adapted for film or television, the second being The Moomins and the Great Flood, although the 1990 Swedish show Moominvalley features the same model house, so it is visually very similar.
The book is dedicated to Saga.
- Nel, Philip. "Review of Moomin: The Complete Tove Jansson Comic Strip. Vol. 1, by Tove Jansonn." . ImageTexT: Interdisciplinary Comics Studies. 3.3 (2007). Dept of English, University of Florida. Accessed 2008-09-06.
- Unofficial Translation (by Teresa Ronayne): "An Unwanted Guest"