|This article is about a/an monster in Mighty Morphin Power Rangers.|
Katherine Hillard's chimp Kelly was transformed into Sinister Simian by Lord Zedd. Sinister Simian's scratches would reflect her face on the Ranger's chests. Alpha 5 tried to fight her but she scoffed at his lack of battle prowess. Returned to normal with an antidote missile from Blue Shogunzord.
Sinister Simian was present at the auction for the Pink Quasar Saber at the Onyx Tavern.