directed into it. reporter: in a bona fide assign tifk study in rochester, new york, 174 newlywed couples were told to watch five romantic movies. monday them love story . love means never having to say you re sorry. reporter: in this group divorce rate fell from 24% to 11%. it does seem simple but at the same time it s brilliant. yes, yes, yes! reporter: so, hang on. could meg ryan save my marriage? oh, god! movies like when harry met sally or sleepless in seattle, those movies don t work so well because the koums only end up at end of the movie so you don t see them getting through day-to-day life together. reporter: among professor s approved movies, a modern tale of step sib lynns into one family yours, mine and ours and indon t proposal.