"Up" begins with a young boy named Carl who is passionate about flying and traveling. He discovers that a young 'tomboy' girl also shares the same passions as he does. Years later, they marry with plans on traveling and living near a waterfall in South Africa. They both find out about the tragic truth that they cannot have children. As the years go by, their plans to move near that waterfall still remains and little by little they save for their trip. Tragically, time after time they find themselves forced to use their savings for much needed expenses. Carl, with tragedy after tragedy, looses his wife, Ellie from natural causes and his life changes from a hopeful life to a lonely and grumpy. Time goes by and everything changes around him as the city builds new buildings around his house and he finds himself disturbed by the fact that those men in charge offer him money to move his home. Carl refuses everytime and suddenly, one incident happens. As the construction men were busy with building, they accidentally push down Carl's mailbox made by him and Ellie. Carl takes this very seriously and ends up hurting a worker, which leads him to court and he is asked to move from the comfort of his home to a retirement home. Carl, surrenders and that very day they came to pick him up to take him into his new abode, Carl, quickly releases what seems to be a million balloons tied to his old house and it rips it right off the ground. Carl is flying his home and his destiny is that place near the waterfall in South Africa! Suddenly, there is a knock at Carl's door. Who could it be? It's a young boy named Russel, a Wilderness Explorer, who had met Carl earlier. Russel is trying to achieve his final badge, assisting the elderly, but wasn't able to help Carl because Carl would reject him. After many tries, the boy was tricked by Carl on finding this mysterious animal and took off looking for it. Carl, thinking he had gotten rid of this boy was now finding himself stuck with him alone with his flying house! A nasty storm catches them in the middle of their journey and they become lost when all of a sudden they appear in an unknown place. Without a compass nor a GPS (who Russel accidently through out the window, earlier) they had no idea where they were! They travel the unknown land by tying themselves to the house to keep it low with their body weight. They come across a large bird (which cannot fly) and Russel manages to convince Carl on keeping this bird, which he names Kevin. In their journey they encounter another friend named Dug. Dug is a dog who carried a translating collar around his neck, enabeling him to speak with his human companions. As they soon find out, Dug's owner is Charles Muntz, Carl's role model since he was a young boy. When they meet up with him, Muntz welcomes them into his airship and with all his dogs invites his new friends to eat dinner with him. Carl soon finds out that Muntz has an ambition to catch a fierceless animal who Carl realizes is Kevin. Muntz and his army of dogs have been trying to catch Kevin for years but have failed. Carl, realizing that Muntz not only wants to capture this beautiful bird but wants to kill Kevin, takes off with Russel and Dug along with his house, running away from Muntz. Muntz's dogs chase them but can no longer after Carl and his friends jump a very deep ditch, reaching the other side. Muntz reaches them, eventually, by Dug's tracking device in his collar. Muntz, quickly sets Carl's home on fire in order to distract him from protecting Kevin. Carl, having deep emotions for his home, tries to save it and succeeds but looses Kevin. Russel, upset with Carl because he didn't do anything to save Kevin, decides not to help Carl anymore on searching for that waterfall. Carl, notices that they have arrived near the waterfall where Ellie had planned to live but with his circumstances Carl enters his house, saddened. As soon as Carl opens Ellie's (his late wife) diary, he notices that what she placed under "My Adventures" was pictures of their lives together. He realizes that she wanted him to move on and create his own adventure. When he steps out of the house, Russel is well on his way to save Kevin from Muntz's hands by grabbing a leaf blower and flying himself to Muntz's airship. Carl, along with Dug, quickly begins to dump out all of his furniture and anything that may keep the house from flying higher and takes off after Russel. They both reach the airship and, with many hardships, manage to save Kevin and return her to her babies. Carl, returns home in Muntz's airship because in the process of rescuing Kevin, he loses his home. He attends Russel's ceremony of Wilderness Explorers and is there when they present Russel his last badge, the "assisting the elderly" badge.
This movie has many messages but the true message is about not holding on to things in this life. We have to move on and continue with our lives. Life is an adventure!