It's My Turn synopsis
A career-oriented math professor, Kate (Jill Clayburgh), begins a torrid affair with a married ex--New York Yankees baseball player, Ben (Michael Douglas), whom she meets at her father's wedding to Ben's mother. Kate isn't single herself. She too is in a long-term relationship to a real estate developer named Homer (Charles Grodin), who has always amicably given her the personal freedom she's professed to crave. But is that what she really wants?