With fantastic visuals and a cyberpunk plot that marries hardboiled action to a lyrical sensibility with a philosophical bent, the original 1995 "Ghost in the Shell" remains one of the must-see classics of Japanese animation. Nine years later, director Mamoru Oshii's sequel is second to the original only because he already pioneered its most innovative ideas.

In the first film, a team of futuristic detectives found themselves unraveling a high-tech conspiracy until one of them, Major Motoko, gives up her "shell" (or body) while her "ghost" (or soul) disappears into the electronic realm. "Ghost in the Shell 2: Innocence" is set years later, in 2032. Major Motoko's old partner, the cyborg Bateau, is on a new case of pleasure robots (called "dolls") who go haywire and kill their owners. Together with his mostly human partner Togusa, he follows a trail that leads to a reclusive hacker.

At least I think that's what happens—the story turns increasingly more bizarre, and the ideas in "Ghost in the Shell 2" are as demanding as the obsessively detailed visuals: characters trade quotes from Milton, Descartes, and the Bible, and while your head is swimming with philosophical aphorisms, the screen is teeming with immense techno-gothic superstructures, strangely biological vehicle designs, and explosive action.

What does it all mean? One thing is clear: Oshii's asks questions about the nature and future of humanity that are worth taking seriously. Cloaked in an overwhelming visual style, it's going to take several viewings to fully decipher "Ghost in the Shell 2," or make sense of its mysterious subtitle. With a film this gorgeous, I won't mind putting in the time.