My main issue with this movie is that it simply isn't humorous. The story revolves around Michael Palin’s character, “Dennis Cooper,” who decides that to win over his beloved "Griselda" (played by Annette Badland), he must journey into the unpleasant city of King "Bruno the Questionable" (Max Wall) and perform a heroic act to demonstrate his value. This task involves eliminating a troublesome dragon - "the Jabberwocky." From the beginning, the intended fairy tale romance feels so unbelievable that it shifts from being somewhat enjoyable initially to genuinely frustrating within about ten minutes. Following this, a group of well-known British actors and comedians attempt to make the film passably entertaining, but the comedy is overly forced and fragmented. Palin puts in effort, yet you can see his weariness as he tries to extend this incredibly thin storyline for 1¾ hours; by the conclusion, even he seems to be wishing it would just end. Those familiar with "Star Wars" may recognize “Darth Vader,” which provides some interest from a celebrity-watching standpoint, but otherwise, it's a flawed and unsuccessful effort at a fantasy adventure, and I was rooting for the dragon all along!

Source on TMDB