I looked specifically for trailers because they show all of the main characters in full swing. I found the 1978 horror/thriller HALLOWEEN by John Carpenter and I saw that the women played the same kind of role as our thriller. In the particular shot above, the three women are the typical young, pretty, vulnerable friends who are not concious of what is to come. They fit the social group of the popular girls a high school that hang out together at each others houses. With our thriller even tough the girls are not together,there is still that feeling that they are united, because of the split screen. With all the girls appearing simultaneously you get the feeling that if something happens to one, something happens to all of them. They fit into the social group of young girls doing there own thing and that they often receive chain messages that they ignore.
In the second shot from HALLOWEEN along with the shot from FOURSQUARE the girls have an innocent look about them.