
In chapter 2, Harry gets a warning from a house elf named Dobby. Dobby talks in third person-kind of like Elmo in Sesame Street. Rowling is able to weave it the tension between Harry and the "you know who" (aka Voldemort) that began in the first book and will continue through the plot of this narrative.
"“Dobby heard tell,” he said hoarsely, “that Harry Potter met the Dark Lord for a second time, just weeks ago . . . that Harry Potter escaped yet again.”
Here you can see that this opens up the conversation to revisit the climax in the first story. Well, Dobby has a warning. Harry is NOT to go back to Hogwarts because bad misfortune is lurking. This sets the tension and now the plot thickens!
On another note, for anybody who has read the series, Isn't the Weasley family just hilarious!