Mysteriet på Greveholm was the 1996 Swedish Julkalender. It was released on VHS in October 1997 and on DVD 19 November 2001. It was voted as the best Julkalender ever in Aftonbladet in 2007. A video game with the same name was released in 1997, and two sequels in 1998 and 2000.

The 2012 Julkalender, Grevens återkomst, is a sequel to Mysteriet på Greveholm.