A psychological thriller should keep the audience on the edge of their seat throughout and make viewers work to solve the mystery themselves. It should include elements like suspense, surprise, controversy, challenging aspects, letting the audience draw their own conclusions, an emphasis on the mental states of characters, thought-provoking themes, intensity, and many twists and turns. Viewers dislike thrillers that are mentally disturbing, have weak endings, unbelievable characters or plots, or storylines that don't flow well. The ideal psychological thriller gets audiences actively involved in trying to figure out what is happening.