It’s no coincidence that the Second Life-style virtual universe thrown into turmoil in “Summer Wars” goes by the name of “Oz.” This spectacular anime entry from Mamoru Hosoda echoes that 1939 classic, in which the Scarecrow, Tin Man and Cowardly Lion served as avatars for Dorothy’s real-world friends. While visionary in its own right — and surprisingly moving to boot — pic feels very much a product of its immediate culture, limiting the toon’s ability to hold up over time or translate beyond Madhouse fans abroad (“War” already won $18 million in local B.O. battles, plus the Japan Academy’s toon prize).

Though hardly a household name in the States, Hosoda launched his career with the “Digimon” franchise and was once in line to direct “Howl’s Moving Castle” at Studio Ghibli (before Hayao Miyazaki took over), instead going on to craft the 2006 cult hit “The Girl Who Leapt Through Time” for Madhouse. Where Miyazaki skews young, Hosoda traditionally appeals to the hard-to-please teen crowd by taking mind-bending ideas and planting them within a relatable contempo context.

In Western terms, “War Games” meets “Tron” in this sci-fi showdown between an all-powerful Oz-based A.I. called “Love Machine” and the handful of young math and computer geeks who suit up to stop it from wreaking nuclear devastation on the real world. As Japanese influences go, “Summer Wars” emerges from the Godzilla tradition — a cautionary tale in which technical misconduct (rather than nuclear mutation) unleashes a seemingly unstoppable man-made force on the country’s panic-prone populace.

Pic’s hero is an awkward yet easily relatable kid named Kenji, a math whiz whose talents seem better suited to the virtual Oz than to his more socially intimidating high school sphere. When class crush Natsuki asks Kenji to accompany her on a family trip to celebrate great-grandmother Sakae’s 90th birthday, he instantly agrees, not realizing Natsuki intends to present him to her family as her future husband — a ruse that forces Kenji, who hides behind an avatar online, to role-play in the real world as well.

After dinner, Kenji receives a long numerical code and stays up all night to crack it. When Kenji sends the solution back from his cell phone, Love Machine steals his Oz identity and sets in motion a massive disruption to the virtual environment, triggering implausible around-the-clock news reports that frame Kenji for the havoc and offer constant updates on what’s happening in Oz.

As “Summer Wars” imagines it, nearly every Japanese citizen has created a cartoony alter ego on the advanced social networking site, inspired by Japan’s Mixi service. While normal life is depicted in traditional anime style, Hosoda blends hand-drawn and staggering CG visuals to give Oz a unique look. The meticulously art-directed environment hovers in empty white space, its many activity centers orbiting a giant abstract face (a cross between a religious shrine and
Takashi Murakami’s massive pop sculptures).

For Hosoda, the trick is finding the proper balance between real-world emotional drama (Natsuki is a frivolous girl, but wise old Sakae swiftly emerges as a character we care deeply about) and the more conventional world-in-jeopardy thrills of Oz. The script implausibly solves its split-personality problem by situating all the key players at Sakae’s house: Love Machine was designed by Natsuki’s uncle, while its star rival, virtual kickboxer King Kazwa, is operated by her cousin Kazuma (whose contributions, which hinge on the confusing Koi-Koi card game, add some nice female empowerment to the mix).

Somewhat surprisingly, Hosoda handles the sentimental scenes best — grounding what might have seemed a throwaway sci-fi parable in the context of a deeper story about members of a once-powerful Japanese clan coming together (with the help of several million virtual friends and a 200-teraflop supercomputer) to restore order.

‘Summer Wars’ Review: A Spectacular Anime Entry from Mamoru Hosoda

Animated - Japan

  • Production: A Warner Bros. Japan release of a Madhouse, Nippon Television Network Corp., Kadokawa Publishing Group production. (International sales: Nippon Television Network Corp., Tokyo.) Produced by Takuya Ito, Yuichiro Saito, Nozomu Takahashi, Takashi Watanabe. Executive producer, Seiji Okuda. Directed by Mamoru Hosoda. Screenplay, Satoko Okudera.
  • Crew: Camera (color), Yukihiro Masumoto; editor, Shigeru Nishiyama; music, Akihiko Matsumoto; art director, Yoji Takeshige; sound (Dolby Digital), Yoshio Obara; character designer, Yoshiyuki Sadamoto; animation directors, Hiroyuki Aoyama, Shigeru Fujita, Kunihiko Hamada, Kazutaka Ozaki. Reviewed at Annecy Animation Film Festival (competing), June 10, 2010. (Also in Sydney Film Festival; 2009 Locarno Film Festival -- competing.) Running time: 114 MIN.
  • With: Voices: Nanami Sakuraba, Ryonosuke Kamiki, Ayumu Saito, Mitsuki Tanimura, Sumiko Fuji, Takahiro Yokokawa.