If the aspect of Strangers from Hell you liked was the dark connection between the two leads then Somebody is definitely for you. Both have two MC's (FL/ML in Somebody and two MLs in SFH) who are not all well in the head, one of them (in Somebody it's the ML) is a killer who becomes interested (obsessed) with the other (FL) due the fact that they find a certain kinship in each other. ("I know that you're just like me and I love it." kind of vibe.) Both endings are relatively the same with the MC killing the other and being irrevocably changed by them.