The owners of the house where Marilyn Monroe last lived and died are suing the city of Los Angeles over what they call “backroom machinations” as part of efforts to landmark the house and save it from a planned demolition.

In a lawsuit filed in Superior Court in Los Angeles County on Monday, lawyers for Brinah Milstein and Roy Bank accused the city of violating its own codes and conspiring with third parties to secure its desired outcome during a hurried process to designate the house at 12305 Fifth Helena Drive a historical landmark last fall.