The first thing you notice about the Japanese romantic comedy “Train Man: Densha Otoko” is its complete lack of snark. Though clearly aimed at teenagers, this unashamedly heartstruck movie is neither obsessed with sex nor driven to humiliate its characters. Compared to those of the average American teen movie, its ambitions are so innocent they’re almost childlike.

A simple tale of beauty, the geek and the Internet, “Train Man” follows the halting courtship of a 22-year-old nerd (Takayuki Yamada) and his subway crush (Miki Nakatani) after he rescues her from an inebriated businessman. Egged on by a Greek chorus of envious chat-room buddies — who wisely advise a total makeover — our hero learns that wooing a woman requires more than an in-depth knowledge of anime. Who knew?

Candy-colored and wide-eyed, “Train Man” is based on Hitori Nakano’s wildly popular novel and directed by Shosuke Murakami with touching tenderness. Though its appeal may be limited to the socially awkward, the movie is unusually perceptive about the attractions of online communities while gently insisting on the superiority of flesh over fantasy. “Train Man” wants us to get off our computers and get out of the house; in a country as technocentric as Japan, the suggestion that it may be time to replace the cyber with the real is not just subversive, it’s downright revolutionary.

TRAIN MAN: DENSHA OTOKO

Opens today in Manhattan.

Directed by Shosuke Murakami; written (in Japanese, with English subtitles) by Arisa Kaneko, based on the book by Hitori Nakano; directors of photography, Yoshihiro Katayama and Shigeki Murano; edited by Junosuke Hogaki; music by Takayuki Hattori with theme song by Orange Range; visual effects by Hirofumi Yoshikawa; art director, Kazuo Yanagawa; produced by Yoshishige Shimatani, Yoshikazu Seki, Yoshiro Hosono and Yoshiro Yasunaga; released by Viz Pictures. At the Imaginasian Theater, 239 East 59th Street, Manhattan. Running time: 101 minutes. This film is not rated.

WITH: Takayuki Yamada (Train Man), Miki Nakatani (Hermes), Eita (Hirofumi, the twister guy), Tae Kimura (Michiko, the housewife), Ryoko Kuninaka (Rika, the nurse), Hiroko Miyake (Tamura, the businessman), Yoshinori Okada (Yoshiga, Geek 1), Kuranosuke Sasaki (Hisashi, Geek 2) and Makoto Sakamoto (Muto, Geek 3).