Cure evil with evil

A wealthy businessman Aristide Leonides is murdered in his own mansion and the people living under the same roof (family & hired hands) are all under suspicion. Everyone could have done it, they all had means and opportunities. They could have been motivated either by anger, jeolousy, love or creed. Young investigator has couple of days to find and arrest the murderer before Scotland Yard burst through the door. Trademark Agatha Christie, and I have always liked a proper mystery, but this one is a bit too slow and boring in its development.