The Liberation of Dobby
Harry Potter and the Chamber of SecretsDobby's journey from an abused house-elf to a free being is a key subplot about slavery and freedom.
increasing
Bearing strength in each event
decreasing
Dobby's Enslaved Life

A Life of Punishment
The Malfoy Servant
Dobby serves the Malfoy family, enduring constant abuse. He punishes himself for any disobedience. His only desire is to protect Harry.
The Secret Acts
Dobby intercepts Harry's letters, seals the barrier at King's Cross, and enchants the Bludger. He does these things out of misguided love, suffering the consequences.
The Plea
Dobby begs Harry to go home, but Harry refuses. Dobby's desperation shows the depth of his loyalty and the horror of his servitude.
The Freeing

A Sock for Freedom
Harry's Trick
Harry gives Lucius Malfoy a sock containing the diary. Lucius throws it away, and Dobby catches it. According to house-elf law, a master's gift of clothes frees the elf.
The Joy
Dobby is ecstatic. He declares himself free and uses his magic to throw Lucius down the stairs. He thanks Harry profusely.
The New Life
Dobby leaves the Malfoys and becomes a free elf. He will later work at Hogwarts. His liberation is a triumph of kindness over cruelty.
before and during the story
after the Chamber of Secrets, late May