Max, a lonely ten-year-old boy in suburban Austin, dreams up an imaginative world called Planet Drool.

Max faces challenges in the real world, including bullying from classmate Linus and his parents' troubled marriage.

Guided by Tobor, a robot toy Max abandoned, they plan to freeze time with the Crystal Heart to repair the dream world.

After escaping, Max obtains the Crystal Heart, but Mr. Electric ambushes them again, leading to Lavagirl sacrificing herself to save Sharkboy.

After sending Sharkboy to revive Lavagirl, he defeats Linus and proposes to create a better dream world together.

[14] Eleven visual effects companies (Hybride Technologies, Cafe FX, The Orphanage, Post Logic, Hy*drau*lx, Industrial Light & Magic, R!ot Pictures, Tippett Studio, Amalgamated Pixels and Intelligent Creatures and Rodriguez's Texas-based Troublemaker Digital) worked on the film in order to accomplish over 1,000 visual effect shots.

The teaser trailer for The Adventures of Sharkboy and Lavagirl premiered in February 2005, during theatrical screenings of Pooh's Heffalump Movie.

[21] Around the time of the film's debut Rodriguez co-wrote a series of children's novels entitled Sharkboy and Lavagirl Adventures with acclaimed science fiction writer Chris Roberson.

They are illustrated throughout by Alex Toader, who designed characters and environments for the film and the previous Spy Kids franchise.

[22] Jeff Jensen of Entertainment Weekly praised another book appearing around the time of the film, The Adventures of SharkBoy and LavaGirl: The Movie Storybook (by Racer Max Rodriguez and Robert Rodriguez), as a far cry from the usual movie storybook tie-in, and also praised Alex Toader's "cartoony yet detailed" illustrations.

It was placed at number 5 at the box office, being overshadowed by Mr. & Mrs. Smith, Madagascar, Star Wars: Episode III – Revenge of the Sith, and The Longest Yard.

[27] The Total Nonstop Action Wrestling (TNA) professional wrestler Dean Roll, who trademarked the name "Shark Boy" in 1999, sued Miramax Films on June 8, 2005, claiming that his trademark had been infringed and demanding "[any] money, profits and advantages wrongfully gained".

[28] In an interview during the 2020 Comic-Con@Home event, Rodriguez confirmed that a character in his then-upcoming film We Can Be Heroes was the youngest daughter of Sharkboy and Lavagirl who has shark powers.