The concept art from the 1966 'Batman' series was absolutely beautiful
The bold style of Batman is part of its enduring appeal. Splashes of bright colors and surreal, dollhouse-like sets amped up the campiness. The pioneering 1966 superhero series is pure eye candy, if not outright museum-worthy pop art. It's no wonder Andy Warhol was a major fan, who even made his own homage film.
So it should come as no surprise that some serious artistic talent was at work on the show. That being said, the preproduction artwork for Batman is surprisingly gorgeous. Illustrator A. Leslie Thomas dreamt up wonderous designs in his works. The results, painted in acrylics with ink, are a little moodier than the lighthearted final product, giving Batman a more, well, traditional Batman feel.
It's no wonder the tone was slightly darker. Thomas, who died in 1983, had a resume that included genre classics like I Was a Teenage Werewolf and Blood of Dracula.
Check out some wonderful illustrations and paintings from the original Batman series and movie. The Batcave is quite recognizable, but Zelda the Great looks rather different in concept. You can find the complete images and more at Batgirl Bat-Trap.
Finally, here is a close-up from a painting Thomas made for Batman: The Movie. It turned up on Antiques Roadshow, where it was estimated to be worth between $6,000 and $8,000.