Setup
1Harry Potter and the Order of the Phoenix · Cleaning Grimmauld Place
The Order finds a heavy locket nobody can open and throws it onto a rubbish pile. It is one cursed object among many in the Black house. Kreacher later steals things from that pile.
2Harry Potter and the Half-Blood Prince · The cave, and a note in a fake locket
Dumbledore and Harry drain the basin and take a locket. It is a copy. Inside, a note signed R.A.B. says the real Horcrux has been stolen and will be destroyed. The initials are not explained in that book.
Payoff
Harry Potter and the Deathly Hallows · Kreacher’s story, then the forest
R.A.B. is Regulus Arcturus Black. He made Kreacher take him to the cave, swapped the lockets, and died there. Mundungus later stole the real locket from Grimmauld Place and lost it to Umbridge. Harry steals it back, and Ron strikes it with the sword of Gryffindor.
People in this thread
8
Harry Potter
Student
GryffindorStudent
Ron Weasley
Student
GryffindorStudent
Hermione Granger
Student
GryffindorStudent
Albus Dumbledore
Headmaster
GryffindorProfessorOrder of the Phoenix
Dolores Umbridge
Ministry inquisitor
SlytherinProfessorMinistry
Kreacher
House-elf
Creature
Mundungus Fletcher
Thief
Order of the Phoenix
Regulus Arcturus Black
Death Eater who defected
SlytherinDeath Eater