Carl Valdemar Jussi Henry Adler-Olsen (born 2 August 1950) is a Danish author who, after following several different courses of study and engaging in various professions, embarked on his literary career with two books about Groucho Marx in 1984.
His bestsellers include the thriller Alfabethuset (Alphabet House) (1997) and, most recently, Journal 64 (2010).
Adler-Olsen's novels have been sold in 36 countries including China, Germany, Japan, The Netherlands, Russia, Spain, Sweden, the UK, and the US. The Alphabet House has also appeared as a movie.
In Germany he has enjoyed particular success, becoming 2011's most popular author (Germans included) with three titles on the top 20 list over several months.