Harry, Ron and Hermione decide not to go back to Hogwarts but to instead search for the remaining Horcruxes so that Lord Voldemort can be defeated once and for all. After the Death Eaters take over the Ministry of Magic and create a scene at Bill and Fleur’s wedding, Harry, Ron and Hermione leave The Burrow and go on the run. After researching the real locket (Horcrux), they discover that Professor Umbridge is now in possession of it. The three of them break into the Ministry of Magic disguised as Ministry workers (using Polyjuice Potion) and retrieve the locket. Harry, Ron and Hermione take turns wearing the locket, because as part of Voldemort’s soul is trapped inside, it makes them angry. The locket seems to affect Ron more than the others and while camping in the countryside, Ron becomes irritated and then leaves. Harry and Hermione go to Godric’s Hollow and are nearly killed by Voldemort’s snake Nagini. A doe Patronus leads Harry to the sword of Gryffindor, one of the few things able to destroy a Horcrux, and after stumbling across Ron, Ron destroys the Horcrux. After a visit to Luna Lovegood’s father, which teaches them about the Deathly Hallows, the three of them have to escape as Death Eaters storm the grounds. Snatchers find the three of them and they are taken to Malfoy Manor where Hermione is tortured by Bellatrix Lestrange, as she is convinced that the sword of Gryffindor should be in her vault at Gringotts. Dobby the house elf helps them, but is killed in the process. The three of them have found out that Voldemort is after the Elder Wand, which is told to win every duel, and steals it from Dumbledore’s grave.
What the movie doesn’t tell you:
The goodbye between Harry and the Dursley’s is much more of an event than what the film makes out. Dudley doesn’t understand why, if things are so dangerous, Harry isn’t coming with them. He tells Harry he doesn’t think he’s a waste of space. They leave out that Tonks and Lupin have gotten married and that she is expecting a baby. The reason the Death Eaters find Harry, Ron and Hermione is because “Voldemort” is a taboo word and the people who say it inadvertently give away their position.