A reconstruction of the bankruptcy of the Banco Ambrosiano bank and its liaisons with the Vatican and the Masonry through its president Roberto Calvi, notoriously found dead under the Blackfriars Bridge in London in June 1982.

When Chiara, a violinist at the conservatory, is brutally murdered after a performance, inspector Maccari is put on the case. Maccari, whose own wife was once murdered by a serial killer, suspect professor Baraldi, the director of the conservatory. But as more fall prey to the killer, Maccari comes to a shocking conclusion...