This Disney/Paramount co-production was almost completely overlooked when released in the summer of 1981--it was eclipsed by a little film called Raiders of the Lost Ark. But it deserves an unearthing, and a nicer DVD release that acknowledges its quality. In it, then-newcomer Peter MacNichol plays an inept sorcerer's apprentice who takes on the responsibility of slaying the massive fire-breather who's been terrorizing his medieval village. After a lifetime of great film performances, Sir Ralph Richardson was somehow denied an Oscar nomination playing MacNichol's magical master, but he got one in 1984 for portraying the patriarch in Greystoke: The Legend of Tarzan, Lord of the Apes (which was very nearly his final film performance).
The direction and scripting by Matthew Robbins is crisp, the moody Industrial Light and Magic special effects are phenomenal (especially the stop motion animation by Phil Tippett), the accurate art direction and photography provide a convincing backdrop for the action, and Alex North's music is quite menacing. This was one of the final works from North, the man who gave us the music for Spartacus, Who's Afraid of Virginia Woolf, and A Streetcar Named Desire. His forboding score is a big reason why Dragonslayer is as fine a fantasy movie as it is. Here's a pretty good fan-made trailer that gets the movie down pat (though it doesn't feature the music from the film, darn it).