I thought that Highlander II and the animated Highlander series were the most horrible incarnations ever created, but Highlander: The Source proved to be truly horrible and might win the award for "Worst Highlander Film Ever." The dialogue reads like unedited fanfic, continuity gaps and non-sequiturs are frequent, the special effects are laughable (as in, so bad that they induce involuntary laughter), and the sword fighting sequences -- which make Highlander what it is -- are too painful to watch.
The sad thing is that there was a lot of potential for this story. The overall effect was a movie worthy of a showing on Mystery Science Theater 3000.
I watched this on the Sci-Fi channel, which means that I didn't have to shell out money for a movie rental or a theater viewing, but it still cost me dearly: two hours of my life have been spent. I could have spent that time at the pub, but oh no. I didn't even have the foresight to bring home some beer to dull my senses and make the movie seem to be enjoyable. Highlander had been that much redeemed since Highlander II that I didn't even consider the possibility that it would be a bomb. That reminds me: this movie demands the development of a drinking game.