Evolutionary psychology PhD student William Costello joins me to discuss Obsession (2026), the sleeper hit film of the summer.

We use the film as an entry point to discuss what psychology has discovered about modern dating and desire. We cover the research showing that men routinely over-perceive women’s interest while women under-perceive men’s, why 60% of romantic relationships begin as friendships, and that nearly half of young men have never asked a woman out. We get into mate poaching (and the “Lancelot effect” of stealing a friend’s romantic partner), why women reject a man’s offer to buy them a drink, and whether the “friend zone” still exists.

We also wade into borderline personality disorder, the “favorite person” phenomenon, and the controversial idea that self-harm can operate as a bargaining strategy. We also cover the unsettling research on what people really want in their opposite-sex friends.

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Why She Won't Let You Buy Her a Drink

Rob Henderson's Office Hours (private feed for [email protected])

Why She Won't Let You Buy Her a Drink