This is based on opinion. Please don't list it on a work's trope example list.
Nightmare Fuel / Rizzoli & Isles
Everything involving CharlesHoyt. In particular, the way he preys on and tortures his victims, most notably Jane, is uncomfortably and disturbingly reminiscent of rape. He also threatens to rape Maura at one point. The guy is just so unsettling and unpredictable in his behavior, it's scary.
The case in "Tears Of A Clown" involves a clown kidnapping children. Sound familiar?
"In over your head" has an absolutely brutal opening in which a teenage girl stumbles upon a drug deal. The scene then cuts to her being interrogated by being repeatedly dunked in a water tank until she drowns. And unlike a lot of opening murders, we get to hear her cries of distress in her last moments.