To me vengeance, I will repay

A detective story about how two groups of interested persons are engaged in a struggle for the inheritance of an unexpectedly deceased art collector. A huge sum of money is at stake. Each of the parties disputes the right to the inheritance of their competitors, claiming that they are involved in the death of a millionaire. To establish the truth and prove their innocence, the rivals, each for its own part, hire detectives to investigate the mysterious death of a collector.