PLOTDeep in the Peruvian jungle, 6-year-old Dora Márquez (Madelyn Miranda), daughter of jungle explorers Cole (Michael Peña) and Elena (Eva Longoria), spends her days going on adventures with her monkey friend Boots, her 7-year-old cousin Diego (Malachi Barton), and imaginary friends Backpack and Map while thwarting Swiper (voiced by Benicio del Toro) the thieving fox. One day, Diego and his family leave to Los Angeles while Dora and her parents remain searching for the hidden Inca city of gold, Parapata.
After 10 years of exploring, Dora’s parents decipher the location of Parapata and choose to send a now 16-year-old Dora (Isabela Moner) to Diego’s high school in Los Angeles while they travel to the lost city. Staying with a now 17-year-old Diego (Jeff Wahlberg) and his family, Dora meets fellow students Sammy (Madeleine Madden) and Randy (Nicholas Coombe). Due to Dora’s intelligence, Sammy sees her as her rival, but Randy is amused by Dora’s intelligence, as well as her being very nice to him, and develops an immediate crush on her. Dora enjoys her new life, but Diego is embarrassed by her eccentric behavior; it culminates in mocking and name-calling by several of their peers when Dora publicly dances to a conga song at the school dance. As Diego walks outside, Dora tries to comfort him, but Diego says that she is not in the jungle anymore, which leads to a fallout between them.
The following day, on a class field trip to a museum, Dora and the others are lured to its off-exhibit archives, where they are captured by mercenaries led by Powell (Temuera Morrison) who fly them to Peru. When they land, a man named Alejandro (Eugenio Derbez), who claims to be a friend of Dora’s parents, helps them escape. In the process, the mercenaries, aided by Swiper, steal Dora’s map. Alejandro reports that Dora’s parents have gone missing and that the mercenaries are searching for them in hopes of getting into Parapata to steal its treasures. Dora resolves to find her parents first with Alejandro’s help, while Diego comes along to look after Dora, with the other teens tagging along in hopes of being rescued.
The group travels through numerous obstacles, including quicksand, Inca ruin puzzles, and attacks from forest guards of Parapata. During the journey, Sammy warms up to Dora and becomes nicer to everyone. Dora and Diego eventually reconcile and Dora notices Diego has a crush on Sammy. After numerous hazards, Dora reaches her parents just outside the borders of Parapata, but Alejandro reveals he was the mercenaries’ leader all along and captures them. The other teens are caught as well, but Boots appears and helps them escape. With Dora’s parents still prisoners, Boots (voiced by Danny Trejo) helps Dora to find her confidence and tells the teens that they need to find the way inside Parapata to acquire the treasure so they can use it to bargain for Elena and Cole’s release.
Inside the hidden city, Dora and the others solve its temple’s puzzles and dodge its traps, bringing them to the central shrine. Alejandro secretly follows them and attempts to steal its central idol himself, but instead falls into a trap. The soldiers guarding Parapata defeat the mercenaries and confront the teens. Dora speaks to their queen (Q’orianka Kilcher) in Quechua, assuring that the kids only came for her parents and to learn. The Inca are grateful for saving their treasures and permit them all to have a single glimpse of their greatest treasure.
After the group leaves, Diego and Sammy become a couple. Dora’s parents and the teens arrive at her jungle home, where the other teens’ parents are waiting and are overjoyed to see them. Her parents discuss going on another expedition as a whole family, but Dora decides to return to school in Los Angeles.
During the credits, Dora and her friends celebrate at the school dance while singing the extended version of “We Did It.” Alejandro remains a prisoner in Parapata. Cole and Elena prevent Swiper from making off with one of their items.