Fede Alvarez used a youthful cast in Alien: Romulus to scare viewers

Fede Alvarez included a youthful cast in 'Alien: Romulus' to create extra terror for the audience.

The 46-year-old director has helmed the new movie in the sci-fi horror franchise and thinks the presence of fledgling stars such as Cailee Spaeny and Isabela Merced will resonate deeply with viewers.

Fede told Variety about his decision to include a young cast: "For me it was a way in to imagine what it would be to a bunch of young people, to grow in one of these colonies in sci-fi and at the end of the world and having to face this creature. They're closer to the audience in a way. They don't know anything about the world they're getting into.

"As a rule of thumb, in horror, the younger people are the tougher it is to watch them die. Let's agree on that. An 80-year-old man dies on screen; you lived a good life, (if a) 12-year-old kid dies in a movie, heartbreak."

Fede wanted to pay homage to the 'Alien' films of the past while also putting a modern spin on the franchise.

The 'Don't Breathe' filmmaker said: "We kept a lot of the perfect elements about those original movies untouched because we didn't need to improve them, but then we had a lot of new stuff. That's what makes it modern and now.

"Hopefully, it takes its place among the other ones, and for me, it's never a bad time in theatres when you're watching an 'Alien' movie. It was such a joyous experience watching it for the first time."

Alvarez was thrilled when the original film's director Sir Ridley Scott praised his offering as "f****** great".

He said: "I couldn't be more grateful that he let us do it."