|Appearances||Layton Brothers: Mystery Room|
|Relations|| Keelan Makepeace (Father)|
Barbarossa Sassina ('Partner')
Alfendi Layton (Enemy)
Diane Makepeace is the daughter of Keelan Makepeace, in Layton Brothers: Mystery Room. She appears in the case File No. 007: The Mystery Rooms, but is indirectly mentioned in the case File No. 006: Kiss Goodbye as being the woman who had killed several members of a gang. Under her disguise of Mariana Etista, she first appears in the case File No. 004: The Walking Corpse. She is out to get Alfendi Layton, who she believes had killed her father four years prior to the game's events.
Diane Makepeace wears a black dress, with a purple rose on the chest of the dress and pearl beads dotted around it. She also wears purple gloves, and a black headpiece which also has a purple rose. She has her long blonde hair tied up in a ponytail.
(To be added.)
Keelan's daughter. Also a killer
"Despite her innocent appearance, Diane Makepeace is a brutal killer of international notoriety. She harbors a deep grudge towards Layton for shooting her father."