The dual engines that power the true crime genre are typically empathy and mystery. You're meant to feel for the victims — a group that can sometimes include the wrongfully accused — while also investing in the solving of a complicated crime.
A reasonably successful true crime doc like HBO's current I'll Be Gone in the Dark works because it combines a whodunit with a portrait of heroic survivors (and, in that show's case, a tribute to late author Michelle McNamara).
Showtime's new docuseries Outcry produces five hours of strange visceral responses, because it isn't particularly mysterious and it generates its empathy in a peculiar way.
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