Michael Douglas has finally admitted to having an affair with actress Kathleen Turner while filming their 1984 action-comedy, Romancing The Stone.

In an excerpt from his upcoming memoir One Helluva Ride, shared by People, the 82-year-old actor claims that he became entangled with Turner during filming, despite still being married to first wife Diandra Luker.

'Kathleen was smart, funny, and sexy with a deep, sultry voice that became her signature. I instantly liked her, and we were immediately attracted to each other,' Douglas recalled.

He then claimed that his marriage to Luker 'was in a bad place' and that he had been having an affair with Romancing The Stone screenwriter Diane Thomas prior to meeting Turner.

Douglas described himself as 'technically married, but separated' when he started his tryst with Turner.  

'Kathleen and I fell hard for each other and began a relationship,' he confessed.

Despite their incredible chemistry, the pair put a stop to things when Luker confronted Turner and said that she and Douglas were still married and together.

'Even though Diandra and I were having major problems in our relationship, we had our own son to think about,' Douglas reflected.

Douglas and Turner went their separate ways and Douglas tried to make his marriage work for the sake of his son Cameron.

While he ended things romantically with Turner, the pair proved to be a box office draw, with Romancing The Stone grossing $115million at the box office.

They reunited a year later for the sequel The Jewel of the Nile, but they kept their relationship strictly professional. 

They did a third movie together in 1989, The War of the Roses, which was another massive box office hit.

Luker eventually filed for divorce from Douglas in 1995 after 18 years of marriage.

According to several reports, Luker walked away with $45million and several homes.

Douglas met actress Catherine Zeta-Jones in 1999 and they married two years later. 

They welcomed son Dylan that year followed by a daughter, Carys Zeta, in 2003.

Douglas and Turner would go on to reunite once again, this time on the small screen in Netflix's The Kominsky Method.

Turner joined the show's second season in 2019 and also appeared in the third and final season in 2021.

They once again denied rumors of a past affair while promoting the series, leaving it as a four-decade secret. 

One Helluva Ride will be released October 6.