Written by Kenzie James

[This article contains spoilers for “Enola Holmes 2,” “Knives Out,” and “Death on the Nile.”]

Murder mysteries have become a popular movie genre in recent years, but as their popularity rose, the mystery waned. It has become easier to identify “whodunit” in recent movies because they all follow a pattern. Many murder mysteries reveal the culprit early because they introduce the character and almost immediately back away; they don’t delve into the character’s story until much later. My theory is that if you pay attention and find this character, you can guess the murderer in the first half of the movie.

I started forming my theory a couple years ago when I consistently guessed the culprit in Hallmark murder mystery movies. I first thought my theory only applied to Hallmark mysteries but later realized it worked for many popular films including “Enola Holmes 2” and “Knives Out.”

Most of the characters in “Enola Holmes 2” are introduced early in the film. Ms. Troy is introduced when Enola sneaks into the match factory office. She remains a minor character until she is revealed as Moriarty at the end of the film. Mysteries like “Enola Holmes 2” follow the detective’s thought process, so the culprit isn’t suspected until the end of the film. This is a good start to identify the murderer: It is commonly a minor character from whom the focus is drawn away for most of the film.

“Knives Out” also follows the same format, allowing the audience to identify the murderer ahead of time. The focus is trickier to follow, as Ransom, played by Chris Evans, is not present at the beginning of the film. He is mentioned at the beginning and focus is drawn away from him until Blanc reveals him as the culprit.

Interestingly, I’ve found that modern remakes of Golden Age novels follow my theory, yet I don’t succeed with the original novels. I think this is because the movies are made in an age where mysteries follow a pattern, though the original story might not. Take “Death on the Nile (2022)” for example.

This movie is more difficult because Jackie was the obvious killer, and she is a culprit. Simon is hard to identify because he has a larger role in the story compared to Moriarty or Ransom, who are both minor characters. However, Simon’s character isn’t explored until Poirot suspects him, so Simon still follows the theory.

I’ve stopped trying to solve the Golden Age novels I read like Hercule Poirot because the plots are more complex than the movies. The novels follow the detective’s unique way of thinking, uncovering hidden relationships and motives. I choose to sit back and enjoy reading a good mystery.

But if you want to play detective, try this theory next time you watch a mystery movie and see if you can solve it faster than the detective.