Goemon is getting married! Well, he was until his bride, Murasaki, was kidnapped by an evil organisation of ninja: the Fuma Clan. Their random is the Shuujoh Vase, the key to a legacy of untold wealth that has been hidden for hundreds of years. And where there's treasure, there's master thief, Lupin the Third!
When word of Lupin's Appearance reaches Inspector Zenigata, he comes out of retirement to put him behind bars once and for all! Can Lupin, Jigen, Goemon and Fujiko rescue Murasaki, unearth the secrets of the treasure, and evade Old Man Zenigata as they try to foil the fiendish plot of the Fuma Clan?
Yasuo Ōtsuka who was working at Telecom Animation Film was the supervisor of this film. Since he was in charge of the OVA, it was his decision to focus on Murasaki and to use his Green Jacket character design as used in Lupin the 3rd Part 1 and The Castle of Cagliostro. Like the Castle of Cagliostro, Lupin's car is the Fiat 500 that was owned by Yasuo Ōtsuka and it was used as a reference during animation.
The animation staff decided to focus more on theatrical style animation with expressions rather than limited animation with mouth flaps. According to Ōtsuka, the idea of the film being lead by the animators was not intentional as the director left at an early stage leaving with just the storyboards to complete.
The production team travelled to the Gifu Prefecture for inspiration, Mt. Shakujo was used as the mountain with the treasure cave while the outdoor soaking pool was used during the car chase.
There were production issues regarding the OVA after the animation was completed. TMS was poorly managed at the time and had money issues, one reason was the development hell of Little Nemo in Slumberland and started to rely on doing outsourced animation for income. According to Monkey Punch who was told by the production team, Yasuo Yamada and the other voice actors were expensive and they needed to reduce production costs.  Some staff members at the time were not keen on Yasuo Yamada's over comical performance of the character and found him "too light". 
The decision was that the usual voice acting cast as well as the sound staff were all replaced, Yuji Ohno was replaced by Kiyoshi Miyaura for the same reason. TMS had used Aoni Production for most of the cast, the chosen cast members were younger except Seizō Katō who played Zenigata. Ōtsuka credited "Mr. K" for this decision.
Toshio Furukawa who played Lupin III in the OVA at first refused the offer due to the strong image of Yasuo Yamada however the producers asked "Unable to do Lupin's performance?". He then accepted the offer but was forbidden to talk about it, he was worried that it might have gone off the record. The other voice actors felt sorry for the regular cast who were not informed and were unaware of their performances.  Despite not being involved regarding production, Monkey Punch did ask the voice actors their approval regarding the change.
When it was broken out to Yasuo Yamada after its release, he complained to Monkey Punch as he was furious regarding Toshio Furukawa's performance. Monkey Punch replied back, "You've allowed this (voice actor change)!" The next day, Monkey Punch contacted TMS and the people involved with the decision had left, it caused him to lose trust in the anime industry.
While the usual voice cast returned for Bye-Bye Liberty - Close Call! due to the outcry from the fans, the relationship between Monkey Punch and Yasuo Yamada became awkward until Yamada's death even though Monkey Punch did apologize to Yamada when they next met.  When Yasuo Yamada died, Monkey Punch cried without the misunderstanding being resolved.
|Lupin III||Toshio Furukawa|
|Daisuke Jigen||Banjō Ginga|
|Goemon Ishikawa XIII||Kaneto Shiozawa|
|Fujiko Mine||Mami Koyama|
|Inspector Koichi Zenigata||Seizō Katō|
|Murasaki Suminawa||Mayumi Shō|
|Baba Suminawa||Kōhei Miyauchi|
|Kotarō Fūma XIV||Masashi Hirose|
- Italian ("Lupin III - La cospirazione dei Fuma")
|Lupin III||Roberto Del Giudice|
|Daisuke Jigen||Sandro Pellegrini|
|Goemon Ishikawa XIII||Antonio Palumbo|
|Fujiko Mine||Alessandra Korompay|
|Inspector Koichi Zenigata||Enzo Consoli|
|Old Man Suminawa||Ettore Conti|
- Diego Reggente as Boss
- English ("Rupan III - The Fuma Conspiracy" / "Lupin the 3rd - The Fuma Conspiracy")
|Lupin III||Robin Robertson|
|Daisuke Jigen||Sean P. O'Connell|
|Goemon Ishikawa XIII||Mark Franklin|
|Fujiko Mine||Michele Seidman|
|Inspector Koichi Zenigata||Marc Matney|
|Old Man Suminawa||Mike Way|
- Paul Johnson as Boss
- Dave Underwood as Kazami
Spanish voice cast (Spain):
- Ricky Coello as Lupin III
- Jordi Ribes as Daisuke Jigen
- María Luisa Roselló as Fujiko Mine
- Juan Antonio Bernal as Goemon Ishikawa XIII
- Juan José Moscoso as Inspector Zenigata
- Mercedes Diemand-Hartz as Murasaki
- Manuel Lázaro as Suminawa
- Antonio Gómez de Vicente as Jefe (Boss)
- Enric Isasi-Isasmendi as Kazami
- French ("Edgar de la Cambriole - Le Complot du Clan Fuma")
|Lupin III||Philippe Ogouz|
(as Edgar de la Cambriole)
|Daisuke Jigen||Philippe Peythieu|
|Goemon Ishikawa XIII||Jean Barney|
|Fujiko Mine||Catherine Lafond|
(as Magali Mine)
|Inspector Koichi Zenigata||Patrick Messe|
(as Inspecteur Gaston Lacogne)
|Old Man Suminawa||Michel Clainchy|
- Philippe Peythieu as Boss
- Bernard Soufflet as Kazami
- Sylvie Feit
- This was the first Lupin animation not to feature Kiyoshi Kobayashi as the voice of Daisuke Jigen who had being voicing him since Lupin the Third: Pilot Film and later projects until Lupin the 3rd Part 6 where he was retired from the role and was replaced in the series.
- In its initial release in the US as well as the English dub, it was known as Rupan III: The Fuma Conspiracy due to copyright reasons regarding the Lupin name. Unusually this did not extend to the UK where this was the first Lupin related video released keeping the original name while later VHS releases such as The Castle of Cagliostro and The Secret of Mamo called the thief Wolf.
- Despite officially classed and produced as an OVA, The Plot of the Fuma Clan did receive a limited theatrical run by Toho. The Theater Ikebukuro in Tokyo and Tamatsukuri Toho in Osaka were two of the theaters that were known to show the OVA.
- When the OVA was released in Japan, there were complaints from fans due to the different voice actors chosen. The fans even directly asked TMS, "Why did you change the cast?"
- Aside from a brief flashback, Zenigata spends the entire movie with his head shaved.
- During the scene where the hallucinogenic gas is released, Lupin changes his character designs as a gag. He switches between The Mystery of Mamo, Lupin the 3rd Part 2, and Lupin the 3rd Part III (episodes 13-34 design).
- The subplot of Zenigata becoming a monk was inspired by a deleted scene from The Mystery of Mamo where he's working at a temple after he hears Lupin is executed.
- Laserdisc (TLL2120, Toho)
- Laserdisc Lupin the Third Theater Box (TLL2199-4, Toho) [custom cover of Goemon sitting with three woman while Lupin looks]
- Laserdisc (TLL2270, Toho)
- VHS (Toho)
- DVD October 24, 2003 (TDV2738D, Toho)
- Laserdisc 1994 Rupan III: The Fuma Conspiracy (AnimEgo) [Japanese with English subtitles]
- DVD June 10, 2003 Rupan III: The Fuma Conspiracy (AnimEgo)
- DVD October 30, 2007 (Discotek Media) [This was Discotek's first Lupin release and is OOP]
- VHS 1993 (Bim Bum Bam Video) [Custom cover, similar except Lupin does not have a weapon or a helmet]
- DVD 2002 Lupin III: La cospirazione dei Fuma (VD-0115 Yamato Video) [Custom Lupin III logo]
- DVD 2002 Lupin the 3rd: La cospirazione dei Fuma (Yamato Video) [Lupin the 3rd Gold Bar logo]
- DVD 2005 Lupin the 3rd Special DVD Collection (1LUP01, DeAGOSTINI/Yamato Video)
- DVD Lupin III Film DVD Collection (Yamato Video)
- VHS ? (WEST 027, Western Connection) [Japanese with English subtitles]
- http://lupinfes2003.fc2web.com/NEW2/interview/ohtsuka/oh03.htm Yasuo Otsuka Special Interview (in Japanese)
- "Fujiko Fetish Club Compilation "ルパンも知らなかった !, Mystery of Fujiko Mine" Shodensha, 1999, pg. 239-240"
- "Lupin the Third, Forever—Yamada Yasuo Memorial (Tokuma Shoten, 1995)"
- "The Plot of the Fuma Clan brochure"
- "The Friday Roadshow that aired with The Mystery of the Hemingway Papers, both Monkey Punch and Yasuo Yamada appeared in guest appearances"
- ElDoblaje entry
- Planete Jeunesse - Lupin III : Film 4 - Le Complot du Clan Fuma (in Francais)