In the film, young sorceresses Lina Inverse and Naga the Serpent reunite to go on vacation to the magical island of Mipross, but they soon find that things there are not quite what they seem and a mighty evil force might be involved.

In another dream, between an event and another, Lina discovers that the old storyteller is the young hero himself and he gained the power of elves, with the ability of seeing the future, and that he was the owner of the legendary Sword of Light.

He and the queen were contacted by the old sage Rowdy in dream and he told them the demon came back again to Mipross and is wreaking havoc in the northern part of the island, blocking the natural flux of hot spring's water, so the girl named Lina Inverse is the only able to beat him.

Lina is initially reluctant, but in exchange of a reward (and Rowdy's promise to reveal the secret location of a hot spring that make things growing up) she and Naga decide to take action against the demon.

Joyrock shows himself in the form of a frog, then turns into a reptile-like creature and reveals to be the Great Master who pulled the strings of the events that took place on the island.

Luckily, Lina manages to travel in the void of time (Naga is missing at this moment), she meets the young Rowdy and, with the help of the Sword of Light combined with Dragon Slave, they finally destroy the demon.

During the end credits, it is shown that the inhabitants of Mipross have erected a statue in honor of the two heroes of the island: the young Rowdy and Lina Inverse.

[9] It was to be included in the collection of digitally remastered Slayers films and OAV series,[10] to be released on Blu-ray Disc in Japan on February 27, 2015,[11] but Bandai Visual briefly cancelled the project, citing production reasons.

The film was presented in anamorphic widescreen for the re-releases and an audio commentary by Cynthia Martinez, Kelly Manison (Naga) and Matt Greenfield was also included on the DVDs as a special feature.

[18] Dave Halverson gave the English language version that "should occupy a slot in any serious collection" a perfect A score in Gamers' Republic, opining it is "emanating everything that is refreshing about anime, from the opening scene to the amazing climax, this is one action/adventure/comedy that never stops delivering on all counts."

[21] Polish fantasy writer Aleksandra Janusz, writing for the magazine Kawaii, hailed the film for its "splendid" animation and opined it was plotwise the best of all Slayers movies.

[23] According to Sandra Dozier of DVD Verdict, the first film is "one of the more laugh-out-loud installments" of the Slayers anime series and "a great introduction" to it, that "definitely earns the 'Essential' label.

"[25] Adam Arnold from Animefringe rated it a B+, opining that "great characters and fun situations make for an unforgettable viewing experience;"[26] Megan Lavey of Mania.com too gave it a B+.

[29] Among some more critical reviews, Marc Marshall of AAW gave it three-and-half stars out of five, stating that "although the mix of weirdness and relatively serious fantasy isn't for everybody, it's quality entertainment if you're in the right mood.