“Trespassers” (*1/2 out of four) was an utterly routine and derivative horror thriller about two bickering couples (Angela Trimbur, Jonathan Howard, Janel Parrish, and Zach Avery) who rent a luxury desert home for the weekend and are hoping to have some fun when a deranged stranger shows up at their door in the middle of the night which leads to a bloodbath and a night of surprises. However, there won’t be too many surprises for anyone who has seen “The Strangers” or “Vacancy” or even “Us” which this movie liberally rips off. Good-looking cinematography (by Noah Rosenthal) is film’s only asset. Fairuza Balk has a minor cameo but she would have been better off counting her “Craft” royalties instead.