In January 1992, Farrow found nude photographs of Previn in Allen's home. Allen, then 56, told Farrow that he had taken the photos the day before, approximately two weeks after he and Previn first had sex. Farrow contends that she broke off her relationship with Allen in 1992 following her discovery of the affair. Previn and Allen dispute that, claiming that Allen and Farrow were no longer involved when Farrow discovered the photos.

Previn graduated from high school and began college in 1991. According to the birthdate the Seoul Family Court assigned her, she turned 21 in October 1991. The judicial investigation during the custody trial between Farrow and Allen concluded that Allen's and Previn's sexual relationship began in December 1991. Mia Farrow's friends have said it might have started in the spring or summer of 1991, before Soon-Yi turned 21.

Previn and Allen married in Venice on December 22, 1997; she was 27 and he was 62.