I think that some of the most vital moments in a story, and it doesn’t matter if that story is told through a visual medium such a feature film or a narrative medium such as novel, are those moment when the character crosses a transformational threshold and enters a new phase of their journey of change.

The best stories are stories about a character’s change where at the end of the tale the character makes choices that would have been beyond them at the start. But along the way to those ultimate transformations the characters cross smaller thresholds that build upon one another until the full transformation takes place and those smaller moments of change are often powerful moments in the story. Here are just a few examples from popular films, and I am going to use older movies because it does dip into spoiler territory.

Jaws

Chief Brody’s transformation from a man who fears water to a man able to venture comfortably forth on the sea is clear but a vital moment of change comes at the hand of Mrs. Kintner. The fishermen have brought in their tiger shark and everyone is celebrating the end of the threat. The moods crashes when Mrs. Kintner slaps Brody because her son is dead, he knew the beaches were unsafe and left them open anyway. It’s a powerful emotional scene and Brody after it cannot go back to who he was before her accusation. It is crossing this threshold that propels him to do a ‘half-assed autopsy on a fish’ and make his first foray onto the ocean and stiffens his spine in encounters with the Mayor. Mrs. Kintner literal slaps his character onto a new path.

Alien

Alien is a tricky beast. The film’s opening acts it hides the identity of the main character. Ellen Ripley, and she didn’t get a first name until the sequel Aliens, a first presents as a person who avoids direct conflict and dangers. She doesn’t volunteer as part of the expedition to investigate the signal, and she’s evasive with Parker and Brett over the bonus situation. Ripley’s first moment of transformation occurs when Dallas and Lambert return with the stricken and ridden Kane. She makes the hard call and denies them access to the ship, almost certainly dooming Kane to death. This is a threshold the character had avoided but faced with an unknown danger she steps across it and after Ash violates the quarantine she is more willing to confront other characters over their misdeeds and actions. The sequence at the airlock is not only vital to the plot, getting the alien aboard the ship, but vital to Ripley’s character development.

When you are craft the important moments of your story look to the one-way door of transformation it is vital to your character.