In Santa Cecilia, Mexico, 12-year-old Miguel dreams of being a musician, even though his family strictly forbids it. His great-great-grandmother Imelda was married to a man who left her and their 3-year-old daughter Coco to pursue a career in music, and when he never returned, Imelda banished music from her family's life and started a shoemaking business.
Miguel now lives with the elderly Coco and their family, who are all shoemakers. He idolizes Ernesto de la Cruz, a famous musician, and secretly teaches himself to play guitar from Ernesto's old movies. On the Day of the Dead, Miguel accidentally damages the picture frame holding a photo of a young Coco with her parents on the family and discovers a hidden section of the photograph showing his great-great-grandfather (whose face had been torn out) holding Ernesto's famous guitar.
Concluding that Ernesto is his great-great-grandfather, Miguel leaves to enter a talent show for Day of the Dead despite his family's objections. He breaks into Ernesto's mausoleum and takes his guitar to use in the show, but once he strums it, he becomes invisible to everyone in the village plaza. However, he can interact with his skeletal dead relatives who are visiting from the Land of the Dead for the holiday. Taking him back with them, they learn that Imelda cannot visit because Miguel accidentally removed her photo from the . Miguel discovers that he is cursed for stealing from the dead, and must return to the Land of the Living before sunrise or he will become one of the dead; to do so, he must receive a blessing from a member of his family. Imelda offers Miguel a blessing, but on the condition that he abandon his musical pursuits. Miguel refuses and attempts to seek Ernesto's blessing instead.
Miguel meets Héctor, who says he knows Ernesto and offers to help Miguel reach him in return for Miguel taking his photo back with him, so that he might visit his daughter before she forgets him and he disappears completely. He helps Miguel enter a talent contest to win entry to Ernesto's mansion, but Miguel's family tracks him down, forcing him to flee. Miguel sneaks into the mansion, where Ernesto welcomes him as his descendant, but Héctor confronts them, again imploring Miguel to take his photo to the Land of the Living. Ernesto and Héctor renew an argument from their partnership in life, and Miguel realizes that when Héctor decided to leave the duo to return to his family, Ernesto poisoned him, then stole his guitar and songs, passing them off as his own to become famous.
Plot Summary from Wikipedia - See more on en.wikipedia.org Text under CC-BY-SA license