Daffy Duck, P.I.: The Case of the Missing Letters is a puzzle game developed by Riedel Software and released on Microsoft Windows. Continue Reading → Jump to a section: Home Releases Credits Overview Walkthrough Achievements Cheats Daffy Duck, P.I.: The Case of the Missing Letters Brainwaves View all → Discussion Article Thought Review 100 Share Daffy Duck, P.I.: The Case of the Missing Letters with others Daffy Duck, P.I.: The Case of the Missing Letters Releases Credits Characters List Overview Walkthrough Achievements Cheats Updates