The Great Blackmail Hunt

The Great Blackmail Hunt is a side quest in Dragon Age: Inquisition.

"Scandalous secrets are everywhere at the Grand Masquerade. Listen in on conversations to gather gossip and scour the palace for incriminating items and notes. The secrets learned could be used to gain power for the Inquisition and the upper hand in the Grand Game of Orlesian society."

Walkthrough
The secrets can be found by eavesdropping, finding secret documents with the search ability, or talking directly to people. It's important to keep eavesdropping in a particular location until you successfully collect a secret. There are 30 to be found.

The first thirteen secrets can be found in the following locations:


 * Palace Garden (main quest starting area) - Find a secret document in the West storage room. (Be sure you get this before entering the palace for the first time because you will not have access to this area again, unless you fight the assassin the end of the mission)
 * Vestibule - Eavesdrop (1/2)
 * Vestibule - Eavesdrop (2/2)
 * Hall of Heroes (rooms where the guests are mingling) - Eavesdrop (1/2) (not on the elves)
 * Hall of Heroes (rooms where the guests are mingling) - Eavesdrop (2/2) (not on the elves)
 * Hall of Heroes (rooms where the guests are mingling) - Ask Duke Germain about his nephew
 * Hall of Heroes (rooms where the guests are mingling) - Speak to the Council of Heralds Vassal and select the "Phillipe is a jerk" conversation option
 * Guest Gardens - Eavesdrop (1/3) (the two noblemen, climb up to the second floor: blood trail topic. Alternatively, you can stand under the balcony near them. Works for both eavesdrops and you do not need to waste the court approval)
 * Guest Gardens - Eavesdrop (2/3) (the two noblemen again, next to them: mage and templar topic)
 * Guest Gardens - Eavesdrop (3/3) (not the two noblemen)
 * Guest Gardens - Find a secret document on the upper balcony
 * Grand Library - Find a secret document (1/2)
 * Grand Library - Find a secret document (2/2)

The next thirteen secrets are found after you have investigated the Servant's Quarters as part of the main quest:


 * Hall of Heroes - Find a secret document on the lower level
 * Grand Library - Find the secret document on one of the tables near the windows on the north facing wall
 * Guest Gardens - Find secret document
 * Vestibule - Find a secret document (lower hallway)
 * Hall of Heroes (rooms where the guests are mingling) - Eavesdrop on the patio by the guards
 * Hall of Heroes (rooms where the guests are mingling) - Find a secret document (1/7)
 * Hall of Heroes (rooms where the guests are mingling) - Find a secret document (2/7)
 * Hall of Heroes (rooms where the guests are mingling) - Find a secret document (3/7)
 * Hall of Heroes (rooms where the guests are mingling) - Find a secret document (4/7)
 * Hall of Heroes (rooms where the guests are mingling) - Find a secret document (5/7)
 * Hall of Heroes (rooms where the guests are mingling) - Find a secret document (6/7) on the patio
 * Hall of Heroes (rooms where the guests are mingling) - Find a secret document (7/7) on the patio
 * Trophy Room - Find a secret document

The final four secrets are found after you have investigated the Servant's Quarters and spoken with Grand Duchess Florianne in the ballroom:


 * Vestibule - Eavesdrop, up the stairs that lead to the Royal Quarters
 * Royal Quarters - Find a secret document (1/3) when you first enter
 * Royal Quarters - Find a secret document (2/3) in the bedroom on the right, up the stair to where you first enter
 * Royal Quarters - Find a secret document (3/3) in the Empress's bedroom

Delivering the secrets to Leliana completes the quest. ''' This must be done before the final confrontation in the Royal Quarters because you will not be able to afterwards. '''

Rewards

 * 128 XP
 * 160 Influence