Things begin with Lupin being summoned to the deathbed of a crime don named Dolune, who sentimentally bequeaths him a rose-colored diamond known as the “Twilight.” There's little time for our hero to examine the gem, however, as a train ride home is interrupted by his perpetually gruff (and perpetually unsuccessful) nemesis, Interpol Inspector Koichi Zenigata. Though the inspector's attempt to arrest Lupin meets with its invariable comedic failure, the train is also boarded by a group of masked, cyber-suited thugs and a whip-wielding she-man named Sadachiyo. They're after Lupin's diamond, of course.

After escaping, Lupin's intrigued enough to follow his attackers' trail to Morocco, where he meets up with the remaining Lupin III regulars: his gun-toting, pointy-bearded cohort Daisuke Jigen, the coolly reticent samurai Goemon Ishikawa, and Fujiko Mine, Lupin's scheming, generously endowed girlfriend/rival. He also encounters Lara, a cute, bandanna-wearing young woman who's a member of an oppressed regional tribe called the Gelts. While falling in with her rebel organization and evading the long arms of Zenigata and the local law, Lupin uncovers the history of the Twilight as well as a plot involving a violent Geltic sub-faction, the members of which look like Aztec versions of Ku Klux Klansmen.

The Secret of Twilight Gemini does its best to assemble a classic Lupin escapade, blending in sudden plot twists, a steadily unfolding mystery, and plenty of opportunities for Lupin to strut his cunning and gentlemanly charms. Unfortunately, it never quite comes together. There's an interesting backstory (and a semi-subtle hint at Lupin's origins), but the script is simplistic and littered with under-explored plotlines about the Geltic underground, a religious prophecy, and a grudge involving Goemon and the effeminate, whip-happy Sadachiyo. The madcap, implausible action of other Lupin films is seldom found here, and Zenigata, Jigen, and other regulars aren't as interesting as usual.

Yet there's one thing Twilight shows more than other Lupin specials: lots of naked women, front and center. There's a gratuitous scene of Lara bathing, and a relatively explicit sex scene featuring Fujiko and Lupin (who are, of course, interrupted by the villains). Unfortunately, an interrogation between Sadachiyo and Fujiko strays too far into sadism to be anything but disconcerting. When Fujiko screams “You pervert!” at him, she may as well be addressing the director.

Twilight somehow remains fun to watch on the whole, and I think it's largely due to Lupin himself. Like some lanky, unsophisticated, and goofily efficient James Bond, he's never without a charismatic air as he out-foxes Zenigata, evades a horde of cyber-thugs, or fails to resist Fujiko's duplicitous advances. Yet even he can't elevate an often lazy script. Director Gisaburo Sugii (Street Fighter II: The Animated Movie, Night on the Galactic Railroad) cribs a little too much from The Castle of Cagliostro and also lets a decent amount of Twilight's time slide into a protracted, pointless musical interlude and a quicksand-centered sequence that rapidly goes from vaguely funny to just plain stupid.

For newcomers to Lupin flicks, FUNimation handles the dub surprisingly well. Sonny Strait (Krillin in Dragon Ball Z) plays Lupin with all of the required gusto, while Mike McFarland (Master Roshi) and Christopher Sabat (who's also the ADR director) fit Goemon and Jigen just as well, respectively. Philip Wilburn's a convincing Zenigata, and Meredith McCoy (Android 18 in Dragon Ball Z) has Fujiko's practical side down pat, though not her sultry one. This time around, however, the most striking voice may belong to Zenigata's only ally, an elderly policeman who sounds exactly like Droopy. The Japanese actors are as good as ever, even if Kanichi Kurita may never truly replace the late Yasuo Yamada as Lupin.

While it's nice to see Lupin in capable hands, FUNimation needed something more substantial for his debut. With its standard story and too many fumbled moments, The Secret of Twilight Gemini is far from the gentleman thief's finest outings, and it's entertaining only in an entirely forgettable way. Apart from the nudity, that is. And I'm not sure that's a compliment.