I was curious about what Twins (1988) might be like if it were a horror film instead. So I asked ChatGPT to write a memorable scene. This is what it did (my comments in brackets):

The scene opens with Julius and Vincent running through a dark, abandoned laboratory. They've just escaped from the facility where they were created, and they're being chased by a group of scientists and government agents. [This was initially confusing. In the film, they grow up separately. So I wondered, Why are they in the lab? Did they grow up in the lab? Definitely a different take.]

As they run, Julius turns to Vincent and says, "We have to split up! I'll lead them away and you get to safety!"

Vincent nods, and the two brothers part ways.

Julius runs down one corridor, dodging bullets and narrowly avoiding capture. But as he turns a corner, he's met by one of the scientists, who grabs him by the arm. [This actually wouldn’t work bc Vincent in the film is super strong and knows karate and stuff. Maybe it’s not a scientist but a Fed w/ a gun.]

"Gotcha," the scientist says, with a sadistic grin on his face.

Julius struggles, but it's no use. The scientist has him pinned. [Definitely wouldn’t work. One could switch out Julius for Vincent, but there’s a particular reason, coming up, why not.]

But just as the scientist is about to administer a sedative, Vincent appears out of nowhere, his eyes glowing with an otherworldly power. He lunges at the scientist and rips his throat out with his bare hands. [Vincent should definitely be the monster, not Julius; Julius represents purity and what is good while Vincent is corrupt.]

Julius watches in horror as Vincent turns to him, his face twisted into a monstrous snarl.

"Vincent, what have they done to you?" Julius whispers.

Vincent doesn't answer. He only gives a deafening scream and charges towards Julius.

This scene would set the tone for the movie, introducing the audience to the stakes, the main characters and the twist of one of the twin being a monstrous creature. It also presents the action and horror elements that would be expected of a science fiction horror movie.

Honestly, that’s pretty good. Not very original, but decent. It’s a great writing prompt. I wonder what happens next. Maybe there’s something in Vincent that stops him from attacking Julius, a brotherly instinct; and he runs off. Next, Julius has to find him - before they do!

Have to say, though, as a writer, I hope I’ll still be able to write and sell fiction once this thing gets really good, which won’t take too long, in my view . . .