The video game series King's Quest has a small, mostly obscure Extended Universe which consists of two sets of novels:
- The various versions of the King's Quest Companion by Peter Spear. Part walkthrough/hint book, part novelization, and part side stories, it has a Literary Agent Hypothesis format which pretends that the events in the games really happened and were told by the various characters to the Companion's author. It contains a lot of extra details and backstory not present in the games and made up entirely by the author, which have a Sure Why Not sort of semi-official status and are often treated as canon by the fandom.
- Specifically, the scribe Derek Karlavaegen has taken up residence in Mannannan's house and is making use of the magic computer to literally e-mail people in our world (notably Peter Spear). People in each world can also dream of each other, which is how Roberta Williams was inspired to create the games in the first place.
- Three licensed novels, each starring a different main character from the games. The marketing blurbs on the books imply they were originally supposed to be the start of a much longer series of novels (possibly even eventually including other Sierra games), but for whatever reason only the three were ever made. They are:
- King's Quest the Floating Castle, which takes place somewhere between King's Quest IV and King's Quest VI (most likely before King's Quest V). It stars Alexander, who has to embark on a trip to rescue his father's soul after it's stolen by an Evil Sorceror in the eponymous castle.
- Kings Quest Kingdom Of Sorrow, which takes place at some point between King's Quest II and King's Quest III, when Rosella is a very small child. It features Graham in a quest to save a kidnapped fairy queen and bring spring back to the land.
- Kings Quest See No Weevil, which also takes place between II and III, though later than Kingdom of Sorrow. It stars a pre-teenaged Rosella, who attempts to rule over Daventry herself while her parents are at a wedding, and runs into some... issues in the process.