Several members of the Order escort Harry to King's Cross station to catch the Hogwarts Express. Moody is annoyed that Sturgis Podmore has not turned up, and Sirius goes against Mrs Weasley's protests by accompanying Harry to the station while disguised as a dog. On the train, Harry worries about whether the Hogwarts students are believing the Ministry's smear campaign against him. He joins Neville and Ginny in a train compartment and meets Luna Lovegood, a {{Cloudcuckoolander}}. She reads ''The Quibbler'', a magazine filled with stories that are unbelievable even by wizarding world standards.

Harry has a brief and rather embarrassing encounter with Cho Chang, whom he fancies. Ron and Hermione return after carrying out their prefect duties. Malfoy, who has also been made a prefect, turns up with Crabbe and Goyle and acts his normal self. He also hints that he knew that the dog at the station was Sirius in disguise. When the train arrives, it turns out that Hagrid isn't there. The carriages to take students to the school are being pulled by sinister-looking winged horses. Harry realises they are invisible to most people apart from him and Luna.