What happend in Harry Potter and the order of the poenix?

Answer 1

In OOTP, Harry and Dudley are attacked by dementors in Little Whinging and Harry conjures a patronus to fend them off. He is expelled from Hogwarts, but after Dunbledore pulls some strings he is allowed a hearing. He is cleared of all charges but while he is there he sees Mr. Malfoy talking to Fudge outside of a mysterious door. Ron and Hermione are chosen as prefects, so on the train Harry sits with Ginny, Neville, and a nice Ravenclaw named Luna Lovegood who is often made fun of because of her spacey behavior. The empty Defense Against the Dark Arts post is filled by a cruel Ministry witch named Dolores Umbridge who lies to the students about Voldemort's return. Harry repetitively tells the truth and receives detention where the lines he writes on paper appear on the back of his hand in blood. Hermione urges Harry to teach a select group of students real Defense, and after a meeting in the Hog's Head, Dumbledore's Army is created. Harry and Cho Chang take it to the next level for a while, but after a bad date in Hogsmeade, they fall apart. Harry, Fred, and George, are banned from quidditch by Umbridge after defending Mrs. Weasley's weight from Draco Malfoy. Harry wakes on Chrismas Eve in the middle of the night after having a realistic dream about being a snake that attacks Mr. Weasley outside of the mysterious door that Fudge and Mr. Malfoy were talking outside of. He alerts McGonagall and they go to Dumbledore's office where Harry is then taken to Snape's office for Occlumency lessens, or lessons to close his mind to Voldemorts control. After Harry takes his O.W.L.s he sees Sirius being tortured by Voldemort in the depths of the Ministry behind the door he saw in the dream. He alerts Ron and Hermione and after getting caught trying to use Umbridge's fire to check if Sirius is at Grimmauld Place, they escape to the forbidden forest with Ginny, Neville, and Luna, who comes up with the idea of using Thestrals, or flying horses of some sort, to get to the Ministry. They arrive at the Department of Mysteries where the door is and after going through many rooms where the kids receive various injuries, they arrive at the place where Sirius should be and they find that neither he, nor Voldcemort is there. Neville points out a crystall ball looking object labelled with Harry's name on it and Harry picks it up only to be attacked by varios Death Eaters. The Order of the Phoenix arrives after Ron, Hermione, Ginny, and Luna are all either knocked out or unable to walk. They all fight over the prophecy until Sirius is killed by his deranged cousin Bellatrix. Voldemort attempts to take over Harry's mind but Harry fights very hard and defeats him. They arrive back at Hogwarts and mourn Sirius' death. Harry is feeling proud of his friends, old and new, for being loyal and fighting alongside him.

Answer 2

Well, at the beginning Dementors (creatures that suck all happiness out of you; if they "kiss" you, they take your soul) attack Harry's neighborhood. In order to save his cousin, Harry performs the Patronus charm to ward them off. Harry is accused by the Ministry of Magic for using magic without a reason out of school, so Harry has to attend a hearing.

During this time, the Ministry doesn't believe Harry when he says Voldemort is back, so they give him a harsh time, but all charges are cleared. Meanwhile, the old Order of the Phoenix, a secret group of witches and wizards (including the Weasleys and remaining Marauders) are coming back together to help conquer Voldemort.

Harry goes back to school, where many people are wary of him and think he's a madman (again). The new Defense Against the Dark Arts teacher, Professor Umbridge, is from the Ministry and is a terrible person who wears pink all the time and is, as JKR puts it, like "poisoned honey." She refuses to teach anyone actual Defense, so Harry, Ron, and Hermione put together a group of students called Dumbledore's Army. They have a great time learning from Harry, though it is totally illegal. Then Cho Chang's friend, Marietta, tells on them and Dumbledore is arrested and Umbridge made Headmistress.

Meanwhile, Cho Chang is Harry's constant attraction. They finally kiss while Cho cries over her old boyfriend who died, Cedric Diggory. Later, they fight and fall apart, and Harry goes for Ginny in the end, but that's Book 6.

Also, Harry starts to have dreams in which he is with or is Voldemort. These actually are happening, and it seems like (and is later proved) that Harry can see images in Voldemort's mind. Dumbledore has told Harry to block out these images but Harry is lazy and sees no reason to, especially with Dumbledore not speaking to him much (for his own good).

But Voldemort realizes the connection between minds and manipulates it. He gives Harry a fake vision of Sirius captured by Voldemort in the Ministry of Magic. Harry has, as Hermione puts it, a "bit of a saving-people thing," so he rushes to Sirius' rescue (after sending Umbridge off with a bunch of hungry centaurs) and finds a prophecy about himself in the Department of Mysteries in the Ministry. He picks it up, and therefore undoes a charm, and the Death Eaters (Voldemort's supporters) come and try to take the crystal ball from Harry. Harry, Ron, Hermione, Ginny, Neville, and a new dreamy Ravenclaw, Luna, put up a fight and are losing when the Order and Dumbledore himself arrive. Sirius, who had come to the rescue, is killed by his cousin, Bellatrix, the leader of the Death Eaters.

Then Voldemort himself comes, and has an epic battle with Dumbledore. Dumbledore wins, and Voldemort disappears just as the Minister of Magic comes and sees him for himself, to know he is alive again.

Harry talks to Dumbledore in his office later on, and the Headmaster explains a lot about what Harry should have known ages ago.

Hope this helped, sorry it was so long (I'm a Potterhead to an extreme).