Katharine McPhee and Michael Morris may have some explaining to do, after they made out in public: They are both married, and not to one another. McPhee, 29, became well known after being a contestant on the fifth season of "American Idol," in 2006. She went on to pursue acting, and in 2011 was the lead in the NBC musical drama “Smash.”

(View pictures here.)

Morris is her former “Smash” director. He has been married to Mary McCormack since July 2003, and they have three daughters together. McPhee has been married since 2008 to 47-year-old Nick Cokas.

She and Morris were not even trying to hide their lip-lock, doing it in broad daylight while in Los Angeles. They even held hands as they took a stroll and looked quite smitten with each other. 

Sources tell TMZ that McPhee has been separated from Cokas for six months, and the two are not living together. However, it is unclear what the status of Morris’ relationship is with his wife.

If there is an affair taking place, it would not be the first time such an incident occured in Hollywood between a director and a member of the cast. Last summer, actress Kristen Stewart had an affair with "Snow White and the Huntsman" director Rupert Sanders while she was in a relationship with “Twilight” co-star Robert Pattinson. Model Liberty Ross, who was married to Sanders at the time, later filed for divorce. The pair married in 2002 and have two children together. Stewart and Pattinson have also since split up.