Paramount Pictures released a featurette for Smile 2 on Thursday.
"I knew that if I was going to approach the sequel, I needed to find a character that I could find something thematic to explore there," he said.
In the Smile franchise, an evil being overtakes its victims and forces them to kill themselves before the eyes of the next target.
"The trick to unlocking it was discovering the character Skye Riley," Finn said. "Skye is this famous star who is surrounded by people and yet she's incredibly alone. It's a frightening situation for anybody to be in."
Naomi Scott will portray Riley."It really does run the gambit of a more internal movie to just being completely unhinged," Scott says in the featurette.
Finn said that his sophomore film will be "10 times bigger" than the first, with more blood and more nastiness.
Smile 2 drops in theaters Oct. 18.
