TV Guide interviewed Bruno Heller and he talked about why the seven suspects might be Red John.
We asked Heller to make a case for each of the seven suspects. "All of those guys have reasons to hide aspects of their personality," he says. "It's just a question of whether they're hiding for ordinary prosaic reasons or for sinister, evil reasons."
Ray Haffner (Reed Diamond): Heller characterizes former CBI supervisor and cult member Ray Haffner as "the sort of Richard Gere-as-villain type. Smiling, charming. Maybe seems a little too shallow to be a serial killer, or too light. ... With Haffner, he always seems smiling and cheery but there always seems to be a dark cloud behind that smile. That, more than anything, would be what made me suspicious of him."
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