The Jet VTOL ship from Ultraman's Science Patrol descends out of the sky toward Earth, as a school girl, carrying her randoseru, observes from behind a tree. The Science Patrol offer the girl a cup of water and ask her to deliver it to "DAICON". The girl salutes and races away, but she quickly experiences trouble as Punk Dragon blocks her path. He summons a mecha from Starship Troopers, and it and the girl begin battling. The girl tosses the mecha aside and Gomora rises from the earth. Using a booster concealed in her backpack, the girl flies up into the sky and evades Gomora's blast, with the mecha flying after her. They continue their battle in mid-air. A blow from the mecha sends the girl falling, imperiling her cup of water. At the last moment, she has a vision of the Science Patrol and regains consciousness. She snatches the cup before it crashes to the ground. Resuming her battle with the mecha, she catches one of its missiles and hurls it back at the mecha, causing a huge explosion. The destroyed mecha launches a rocket, summoning Godzilla with the Ideon symbol. With King Ghidorah and Gamera chasing her, the girl flies through the air with her jet-propelled backpack. A Star Destroyer, a TIE fighter, and Martian fighting machines from the film The War of the Worlds (1953) cross the background. Reaching into her backpack, the girl pulls out a bamboo ruler, which magically becomes a lightsaber. After slicing an Alien Baltan in half, the girl launches a number of miniature missiles from her backpack. Hit by one of the missiles, a Maser Tank from the Godzilla series catches fire. The Atragon breaks in two as the Yamato, the USS Enterprise, an X-wing fighter and Daimajin explode in complete chaos. The girl pours her cup of water on a shriveled daikon buried in the ground. As the daikon absorbs the water, it turns into the spaceship Daicon. Bathed in light, and now wearing a naval uniform, the girl boards the ship, where the film's producers, Toshio Okada and Yasuhiro Takeda, sit at the controls. As the landing gear retracts, Daicon departs for the far reaches of the universe.
The Daicon IV Opening Animation begins with an abridged, 90-second retelling of the Daicon III Opening Animation set to music by Kitarō. After this, "Prologue" by Electric Light Orchestra is heard, while the lyrics appear against a starfield and an outline of the spaceship Daicon passes in the background. The film proper begins as "Prologue" segues into "Twilight", the song which follows it on the album Time.
The girl from the previous animation is now an adult, wearing a bunny costume. She fights off a multitude of sci-fi monsters and mobile suits then jumps into a throng of Metron Seijin and tosses them aside. She is then in a lightsaber duel with Darth Vader, with Stormtroopers sitting in the background and the Death Star enshrined in one corner. From atop a cliff, a xenomorph with artificial legs, wielding the Discovery One, knocks the girl down with an energy burst and the Dynaman robot attempts to crush her. The girl lifts the Dynaman robot off her with superhuman strength and smashes it against a cliff. The Stormbringer suddenly appears in the sky, and the girl jumps on it, riding it like a surfboard. A few scenes unconnected to the main plot are shown, such as Yoda as Yū Ida given a Japanese comedy routine with various characters in the audience. The girl is still riding the Stormbringer when she runs into a formation of Ultrahawk 1's. Then the Yamato, the Arcadia attached to the transformed SDF-1 Macross appear, along with an exploding VF-1 Valkyrie variable fighter from Macross armed with a Gundam-style beam saber. An air battle unfolds in an otaku coffee shop. The girl is then seen in a world filled with American comic superheroes. A host of machines and characters (from The Lord of the Rings, Conan, Narnia, Pern, and others) fly past her into space, including a Klingon battle cruiser, the moon ship from H. G. Wells' First Men in the Moon, the Millennium Falcon, Lord Jaxom and the Thunderbirds. Once back on land, the girl jumps off the Stormbringer and it splits into seven parts, which fly though the sky spewing smoke in seven colors. A sequence of famous spaceships crashing into each other is shown. Then, suddenly, "what could only be described as an atomic bomb" explodes over an unpopulated city, leaving behind a flurry of sakura petals. Successive upheavals of the Earth give birth to new worlds. As a beam launched by the Daicon traverses the sky, lush greenery sprouts and grows. The camera then pans over a massive crowd of fictional characters, the sun rises, the camera zooms out to the solar system, and the film ends with an image of the Daicon logo.
Originally, the productions were intended to be shot in 16 mm film, but both were shot in 8 mm film instead and were completed only the morning before their debut. In order to pay off the debts of the productions, video copies of the animation were sold. Eng declares this as the first example of original video animation (OVA) predating Dallos. Kazutaka Miyatake of Studio Nue originally designed the mecha that appears in the Daicon III clip chasing the little girl for a Japanese edition of the military science fiction novel Starship Troopers novel in the early eighties.
Only three people were involved in the production of Daicon III, Hideaki Anno, Hiroyuki Yamaga and Takami Akai. Takeda, who was a part of the group, explains in Notenki Memoirs that Anno knew how to make anime, but he never worked with animation cels. They were referred to Animepolis Pero, an anime hobby store chain, but they found that the cost of the cels were too expensive, so a single cel was purchased and taken to a vinyl manufacturer in east Osaka, where they purchased a roll for 2000 yen. After cutting and preparing the vinyl cels, they discovered that the painted cels would stick together when stacked and dry paint would peel off the cels. To keep costs low, they made their own tap to punch holes in the B5 animation paper used in the production.
The work was carried out in an empty room of Okada's house where their business was also operated. While other people were present, the work was shared and Anno, Akai and Yamaga worked full-time on the production, the direction was not professional, but Takeada attributed Okada as the producer, with Yamaga directing, Akai doing character animation and Anno as the mecha animator. Takeada also said other individuals were involved and were used to trace cels or paint cels as needed, but still credits Yamaga, Akai and Anno with the production itself. Filming was done by a camera on a tripod and frames were called out by Anno because the production lacked timing sheets.
Osamu Tezuka did not see the opening film at Daicon III, but was shown the film by Akai and Yamaga later that night. After watching the film, Tezuka remarked "Well, there certainly were a lot of characters in the film. ... [T]here were also some that weren't in the film". Akai and Yamaga later realized the omission of Tezuka's characters; they were subsequently used in the Daicon IV animation. According to Toshio Okada, the theme of water in the opening represented "opportunity" and Lawrence Eng, an otaku researcher, describes the theme as, "... making the best use of one's opportunities while fighting against those who would seek to steal such opportunity away."
The production facility for Daicon IV was in a dedicated studio in a building called the Hosei Kaikan that was owned by a textile union. Takeda defined it as a literal anime sweatshop, the building was shutdown at 9:00 pm and a majority of the staff would be locked inside and working through the night without air conditioning. The Daicon IV film officially credits a production crew of twelve people. Hiroyuki Yamaga directed the production of Daicon IV with Hideaki Anno and Takami Akai as animation directors. Toru Saegusa did the artwork and the animations were done with Yoshiyuki Sadamoto, Mahiro Maeda, Norifumi Kiyozumi; additional animation was provided by Ichiro Itano, Toshihiro Hirano, Narumi Kakinouchi, Sadami Morikawa, Kazutaka Miyatake. Originally, Daicon IV was supposed to be fifteen minutes long, but the difficult production resulted in the cut time.
The Daicon III film was reported on in Animec magazine which resulted in requests for the film to be released publicly. In order to pay off the debts from producing the film, the decision was made to sell 8mm reels of the film and videos. Additional original artwork and the storyboards were included in the release. The sale paid the debts and the profit would be used to produce Daicon IV.
Due to copyright problems an official release of the animations has proven impossible. For the American release of the film, the rights to use of the Playboy bunny costume was denied and the rights to Electric Light Orchestra's music was consequently not sought. However, a laserdisc featuring Daicon III & IV Opening Animation was unofficially released in Japan as bonus material to a ¥16,000 art book of the animations. This laserdisc is considered rare and highly valuable among collectors, easily fetching prices over a thousand dollars on online auctions.
Since its release the animations have been referenced several times in Japanese media productions, especially those focused on otaku culture. Clips and characters from the animations appear in the 1991 Gainax OVA Otaku no Video. The opening sequence of the Train Man Japanese TV drama series from 2005 was inspired by and uses the Electric Light Orchestra theme and the lead character from the Daicon IV film. In episode 5 of Gainax's FLCL, titled "Brittle Bullet", Haruko, wearing a red bunny suit, flies in on a bass guitar and yells "Daicon V!" before attacking a giant robot with a slingshot.
At Fanimecon, Yamaga said, "[The openings are] a source of pride and something you want to strangle." Akai who wants to produce better films stated, "I don't want to see them for a long time. Just thinking about them sends shivers down my spine." Lawrence Eng stated that without the Daicon animations, Gainax might never have existed. In 2001, the anime magazine Animage ranked the Daicon animations as the 35th of the "Top 100" anime of all time.
Gainax revealed the details of a new campaign to celebrate Daicon Film's 33rd anniversary. The new project is named "DAICON FILM 33" and was announced on January 8, 2014. The basis of the project is a "revival of DAICON FILM" and includes the release of several goods inspired by the original films from the eighties.
The project's official site has started accepting pre-orders for the first lineup of memorial goods. A new illustration of the "Daicon Bunny Girl" has been drawn by Takami Akai, the original character designer of the opening animation films and one of the founders of Gainax. The art is now also displayed on the top page of Gainax's official site.