A smart idea hits most of its targets in the macabre comedy "Save the Green Planet!", but veers wildly off-course in the fourth act. Pic about a deranged serial killer who thinks he's helping Earth by killing off supposed aliens works on a variety of levels. Late-night festival slots and fantasy events look to be the best platforms for the movie.

A smart idea hits most of its targets in the macabre comedy “Save the Green Planet!”, but veers wildly off-course in the fourth act. Though certainly not to everyone’s tastes, this looney-tunes pic about a deranged serial killer who thinks he’s helping Earth by killing off supposed aliens works on a variety of levels, from gruesome slapstick comedy through social critique to genuinely chilling Grand Guignol. Unfortunately, it settles for a finale that’s way out of kilter with the teasingly ambivalent tone of the first 90 minutes. As well as “Asia Extreme”-type vid labels, late-night festival slots and fantasy events look to be the best platforms for the movie, which has flopped locally since opening April 4.

First-time writer-director Jang Jun-hwan, who co-penned the script to nautical drama “Phantom, the Submarine” (1999), ransacks a lot of stylistic larders here, from Jeunet & Caro’s grotesque fantasies, through Japanese directors like Shinya Tsukamoto (“Tetsuo”) and Takashi Miike, to Korean helmer Park Chan-wook’s much more controlled but equally black and obsessive “Sympathy for Mr. Vengeance.”

Despite that — and a freshman-helmer’s tendency to try and pack too much into one picture — “Planet!” still conveys an original feel most of the time, thanks to a first-rate perf by Shin Ha-gyun (the South Korean soldier in “JSA”) that exactly mirrors the pic’s unsettling shifts from comedy to drama.

Shin plays Lee Byeong-gu who, unhinged supposedly by watching too many movies like “Men in Black,” is convinced Earth is about to be invaded by aliens from Andromeda. He reckons the leader of the secret advance guard is tycoon Kang Man-shik (Baek Yun-shik), head of Yuje Chemicals. So, Lee and his dumpy, retarded g.f., Sun-i (Hwang Jung-min), a circus performer, kidnap Kang. They imprison him in Lee’s mountain retreat in Kangweon Province, east of Seoul. They have a week to learn the secret of Kang’s “royal genetic DNA code” before the next full moon, which is when Lee is certain the Andromedans will invade.

Stripped to his jockey shorts and tied to a chair in Lee’s baleful basement, the very human-looking Kang suffers all kinds of physical torture but remains disdainful of Lee’s conviction that he’s an extra-terrestrial.

Back in Seoul, the cops, led by the gruff Lee (Ki Ju-bong), aren’t having much luck solving Kang’s abduction. However, a disheveled but clever ex-detective, Chu (Lee Jae-yong), is making headway, secretly helped by a young cop, Kim (Lee Ju-hyeon), who admires him.

What starts off looking like an outre, over-baked comedy starts to develop extra levels after the first half-hour. Kang suddenly remembers Lee is the son of a woman who suffered an industrial accident at one of his factories. Claiming Lee is just seeking revenge,Kang tries psychological warfare, telling Sun-i that Lee doesn’t really love her.

That’s less than halfway through the film, which turns even blacker as nagging questions about Lee’s background are gradually answered. Is he on a killing spree to avenge his mom, is he a genuine alien-hunter, or is he just a complete sicko? Chu and Kim then enter the main action, before a major twist at the 90-minute mark sends the pic spinning off into more fanciful regions.

There’s a feeling throughout that there’s actually more backstory to all the characters than ever reaches the screen — which makes “Planet!” a rewarding second sit even when the element of surprise has gone. Small behavioral quirks are revealed on a repeat viewing that make absolute sense in the larger scheme of things, and may have been missed the first time round. There’s also considerable detail in the props and busy production design that simply can’t be assimilated on a single viewing. “Planet!” is far more than just a goofy, macabre comedy — so more’s the pity that it blows the finale.

Production design, from Lee’s rambling, wood-and-corrugated iron retreat to his creepy basements, is immensely detailed, lensed with restraint by Hong Gyeong-pyo. Orchestral score by German-born, Seoul-based composer Michael Staudacher (“Indian Summer,” “Double Agent”) starts to take on a major role at the 70-minute point, with a rhapsodic, mini cello concerto that directly plays against the visuals.

Shin’s performance anchors the movie, but he’s surrounded by a raft of other strong players, from Baek as the indestructible, arrogant Kang to Lee Jae-yong as the rumpled ex-detective. A cat-and-mouse sequence between Lee and Shin, when the former visits the latter’s hideaway, is one of pic’s highlights. Hwang is perfect casting as the podgy Sun-i, and her tightrope dance to the song “Besame Mucho” is another offbeat high point; but her too-easy exit from the action early on rings as a script contrivance.

Original Korean title simply means “Save the Earth!”

Save the Green Planet!

South Korea

Production

A CJ Entertainment release of a CJ Entertainment presentation, in association with Sidus and Discovery Venture Capital, of a Sidus production. (International sales: CJ, Seoul.) Produced by Cha Seung-jae, Noh Jong-yun. Executive producer, Lee Kang-bok. Co-executive producers, Cha, Jeong Hong-gyun. Directed, written by Jang Jun-hwan.

Crew

Camera (color), Hong Gyeong-pyo; editor, Park Gok-ji; music, Michael Staudacher; art directors, Jang Geun-yeong, Kim Gyeong-heui; sound (Dolby Digital), Lee Ji-su; martial arts supervisors, Kim Min-su, Yu Sang-seob; special effects, Jeong Do-an (Demolition); special visual effects, Jang Seong-ho; assistant director, Kim Jong-hun. Reviewed on videocassette, London, April 11, 2003. Running time: 116 MIN.

With

Shin Ha-gyun, Baek Yun-shik, Hwang Jung-min, Lee Jae-yong, Lee Ju-hyeon, Ki Ju-bong.
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