Legal Question in Landlord & Tenant Law in California

You are in a pretty weak position vis a vis the true owner, but depending on the details of how the scammer came to rent it to you, you might be able to impute the conduct of the scammer to the owner. How, for example, did the scammer get keys to give you. Your position really is going to turn on the very specific details of what happened. You need to sit down with a lawyer and go over everything.