intruder, uninvited person
Il y a deux intrus dans la tour.
There are two intruders in the tower.
Monsieur, à quelle heure avez-vous affronté les intrus ?
Sir, at what time did you confront the intruders?
— Once Upon a Time... in Hollywood (2019)
Sachez que je n'aime pas les intrus.
Know that I don't like intruders.
The intruder broke the window.
Capitaine, l'intrus a tenté de communiquer.
Captain, the intruder tried to make contact.
— Star Trek, le film (1979)