The Flight of Dragons
An underrated animated movie from the 80's - based on the books
The Flight of Dragons by Peter Dickenson and
The Dragon and the George by Gordon Dickson, while the film was made by Rankin/Bass.
The story begins in the 10th Century as mankind's growing preference of logic over magic is putting the magical world and all its inhabitants at the real risk of vanishing forever.
To try and preserve it, Carolinus - the Green Wizard of Nature's Realm - summons his three magic brothers to a meeting, where he proposes they combine their powers to create a final realm of magic, which would ensure the survival of magic and in turn mean there will always be magic to inspire man to 'surmount the insurmountable'.
However, Ommadon - the Red Wizard of the Devil's domain - refuses and instead plans to use his darkpowers to make mankind destroy themselves with their science and logic. With the magic brothers forbidden by the ancient laws of enchantment from warring on one another, Carolinus decides to inspire a quest with its mission to steal Ommadon's crown; the source of his powers.
In order to achieve this, Carolinus selects a leader for the quest - an author from the 20th century with a scientific background yet a love of fantasy and dragons.
Outside of the opening theme, there's no musical numbers and the film does have a lot of depth and detail as well as both adult humor and some scary moments - with a fair few death scenes which are either implied or graphically portrayed. It's also got a fairly good voice cast with the talents of Harry Morgan (
M.A.S.H), Don Messick (
Scooby Doo, Jonny Quest, The Transformers), John Ritter (
It, Bad Santa) and James Earl Jones (
Star Wars, The Lion King) as the voice of Ommadon.
If you get a chance, I'd recommend watching it. Here's a fan-made trailer for it and the opening song by Don McLean: