[6] While technically based on the shorts, the film was mainly adapted from the Spanish graphic novel Tadeo and the Secret of the Toactlum, illustrated and co-written by Juan López Fernández (Jan) and written by Javier Barreira, Gorka Magallón, and Gato.

The film was adapted and written by Barreira, Magallón, Ignacio del Moral, Jordi Gasull, and Neil Landau.

The English cast features the voices of Kerry Shale, Ariel Winter, Bruce Mackinnon, Mac McDonald, Liza Ross, Cheech Marin, and Adam James.

Tadeo Jones (Tad Stones in the English version and voiced by Kerry Shale) is a bricklayer who lives in Chicago, working on the construction of the city's subway.

Odysseus Inc., led by the evil Kopponen, (also voiced by Kerry Shale) again tries to steal the key, but Tad and Sara escape their clutches.

After a series of adventures, they find Lavrof and Max Mordon (voiced by Adam James), a famous archaeologist Tad idolizes and Sara's fiancé.

Tad, the Lost Explorer was produced by Lightbox Entertainment, Telecinco Cinema, El Toro Pictures, Telefónica Producciones, and Ikiru Films, and co-produced by Media Networks.

It was distributed by the Spanish subsidiary of Paramount Pictures, in collaboration with AXN, Televisió de Catalunya, Grupo Intereconomía, Mediaset España, and Canal+.

[15] David García voiced the character in the first short film, in which Tadeo Jones does not speak but utters exclamations and murmurs.

Spanish comic book writer and artist Juan López Fernández (known as Jan) made two cartoons to promote the feature film starring Tad,[16] which were used as storyboards.

The character was animated using three forms based on the same geometric shape, one fully clothed, one without hat and shirt, and one wearing only boots and underwear.

It also concludes a section of extras from the movie with the making of, the trailer, video clip, short films, and the design and creation of characters.

[23] The film generally received positive reviews mainly from Spanish critics and audiences praising the animation, action scenes, Gato's direction, and cast of characters.

He called Tad, the Lost Explorer "the best film in Spanish animation history" and praised its visual quality and cast of characters, although he criticized the choice of soundtrack.

"[24] Carmen L. Lobo of the newspaper La Razón gave it three out of five, calling it "a candid story, furiously-paced and strongly influenced by comics, yet stripped of any malicious double meaning."

Grace Montgomery of Common Sense Media rated the film two stars out of five, describing it "lame adventure feels like a low-budget version of a movie […]."

She also noted that the film focuses on plot development and "less on showing the bad guys waving guns around, which starts to feel pretty excessive by the end of the movie.

[11][12] It was co-directed by Enrique Gato and David Alonso,[11] and written by Jordi Gasull, Javier Barreira and Neil Landau.

[11] The second sequel titled Tad, the Lost Explorer and the Emerald Tablet was released in August 2022 and was directed by Enrique Gato.