Insidious: Chapter 3's The Man Who Can't Breathe might the franchise's creepiest villain to date. Director James Wan (Aquaman) and screenwriter Leight Whannell first broke through with their low-budget, genre-defining horror movie Saw. The movie revolved around two men - one of whom was played by Whannell - who are forced into a sinister game by an unseen psychopath. The film was an intense, creative thriller, but the sequels would put a bigger focus on villain Jigsaw's elaborate, nasty traps.
Wan and Whannell followed Saw with Dead Silence, a horror film about an evil puppet. While it featured some eerie visuals and sequences, it was a flawed genre effort that failed to make much impact in 2007. The experience of working with the studio on it also made the duo go back to their indie roots, resulting in 2011's Insidious for Blumhouse. They had total creative control over the film which became a huge success, spawning a series that ran for a further three entries.
Insidious also gave genre fans nightmare fuel in the form of evil spirits and demons like the Bride In Black and the Lipstick-Face demon. Arguably the creepiest - and definitely the most underrated - antagonist of the series is Insidious: Chapter 3's The Man Who Can't Breathe. The third film also marked Whannell's directorial debut and is set before the events of the first two movies. It centers on a teenage girl named Quinn being haunted by a rasping, sinister spirit who first causes her to break her legs in an accident, and then tries to make her commit suicide.
Insidious: Chapter 3 gives no really backstory for The Man Who Can't Breathe - AKA the Wheezing Demon - but it appears he lived in Quinn's building before succumbing to cancer years before. His goal is to bring people back to his corner of the "Further" and imprison them, so they can share in his endless pain. Whannell stated that with The Man Who Can't Breathe he wanted a spirit who was almost a metaphor for cancer and misery, and the character seems to enjoy inflicting pain on the living. He takes the form of franchise heroine Elise's (Lin Shaye) late husband in one scene to fool her into committing suicide too, which backfires.
Insidious: Chapter 3's The Man Who Can't Breathe is designed from the ground up to get under the skin of an audience. He's defined by his wheezing breath, diseased skin, and cruelty, but in contrast to the franchise's other villains like the Lipstick-Face demon or Insidious: The Last Key's KeyFace, he feels all too human. He's bested in the end by Quinn, who is given strength by her loved ones and rips the breathing mask from the spirit's face.