Asshole Victim: Karl Schreyer is roundly disliked by pretty much everyone who knew him thanks to his generally unpleasant behavior and his willingness to steal other people's inventions. Bell describes him as having negative charm.
Elective Mute: Myrtle Raylin, one of the inventors, is deaf and can form words with effort, but finds it simpler to sign, with rare exceptions (such as calling Karl a bastard).
Not Good with Rejection: When Myrtle refused Karl's advances, her fellow inventor "insulted her femininity and mocked her deafness and said that instant mail wasn't really an invention at all but merely a reworking of Edison's stock ticker." He also framed her for his murder.
Wimp Fight: Rival inventors Karl Schreyer and Ernest Harding have an off-screen fight that Harding embarrassedly describes as "a lot of arms flailing about. Neither of us were exactly pugilists."
Xanatos Gambit: The killer knew that either his rival inventors would be hanged for his murder or they would finally have to recognize his intellect if Murdoch did figure out it was Suicide, Not Murder.
