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A fleeing criminal who once would have vanished into a transatlantic crossing can now be outrun by the message itself, because wireless travels faster than any ship. The dawn of instant long-distance communication collapsed the geographic head-start that fugitives had always relied upon, turning escape into a trap.
Dr. Crippen, having murdered his wife and fled disguised aboard a ship to Canada, was recognized by the captain who wired Scotland Yard while Crippen sailed on, unaware. A detective boarded a faster vessel, reached Canada first, and arrested him as he disembarked — the first time wireless was used to catch a murderer.
Marconi advanced wireless telegraphy not by superior scientific knowledge but by stubborn conviction that signals could travel distances the physics of his day declared impossible. Practical breakthrough sometimes comes from an outsider who refuses to accept the limits experts have proven, attempting what theory says cannot work.
The mild-mannered, unremarkable man who blends seamlessly into respectable society can conceal capacity for murder precisely because his ordinariness disarms suspicion. Read social presentation as a surface that may hide rather than reveal — the most domestic appearance can be the most effective camouflage.