Bob and Rhoda Carson are rich and live in the country in Rose Hill mansion. They go to a night club and befriend a young couple, Marty and Charlotte Lanning, who are celebrating their first wedding anniversary and invite them to their mansion for the weekend. When they arrive they are not the only people there, it seems to be a hobby of theirs inviting strangers to their house for the weekend. The three guests have no idea what are their strange hosts are up to but from the things they say and do it bodes evil for Bert, Marty and Charlotte...