The author writes the couple’s first night out was “chaste,” largely because of one complication: Arnaz’s then-girlfriend was arriving in town that night

A new book is resurfacing the tumultuous relationship of Lucille Ball and Desi Arnaz — who were both in relationships with other people when they started their own romance, and who once divorced so briefly that the breakup was invalidated by a judge.

In his new book Desi Arnaz: The Man Who Invented Television, biographer Todd S. Purdum describes how Ball and Arnaz first met while filming the musical comedy Too Many Girls. The two not only hit it off right away, but began a relationship despite the fact both were in relationships with other people — Ball with director Al Hall, to whom she was briefly engaged, and Arnaz with dancer Renee De Marco.

Purdum writes that the couple’s first night out was “chaste,” largely because of one complication: Arnaz’s then-girlfriend was arriving in town that night.

But days later, while out with his girlfriend, whom he had nicknamed “Freckles,” Arnaz spotted Ball at a party.

“That weekend, Desi took Freckles to Eddie Bracken’s rented beach house in Malibu, where he spotted Lucille,” Purdum writes. “She patted the sand beside her and asked him to sit down. ‘I sat down and never went back to Freckles,’ Desi recalled.”

After Ball and Arnaz spent that night together in her apartment, Ball called it off with her fiancé, and Arnaz called it off with De Marco.

“The next day, Lucille called Al Hall to tell him she would have someone collect her belongings from his house, and Desi called De Marco to confess that he couldn’t explain it but had fallen in love with Lucille,” Purdum writes.

The couple married in 1940, but the next few years were turbulent and filled with frequent fights, as Arnaz was routinely caught having affairs.

By the summer of 1944, Ball had had enough, filing for divorce for Arnaz after four years of marriage and leaving the couple’s shared ranch in Chatsworth, Calif.

It was then that Ball sought solace from an unlikely source: the woman whom Arnaz had been dating when she first met him.

“After filing for the divorce, Lucy escaped from the loneliness of the ranch for a time,” Purdum writes. “Incredible as it may seem, she went to live with Desi’s old girlfriend, Renee De Marco.”

DeMarco was at that point remarried to dancer Jody Hutchinson, was living in Hollywood and had become a friend of Ball’s.

By November, the divorce was set to be finalized and just one day before Ball was to appear in court, Arnaz gave her a call, inviting her to a farewell dinner in Beverly Hills. The conversation went well, it seems, as Purdum writes that the two “wound up in bed.”

But the next morning, Ball woke up in a frenzy, telling her estranged husband, “Oh, my God, I’m late,” before he asked, “Where are you going?”

“I told you, I ‘m divorcing you this morning,” Ball replied, before telling him she had to “go through with it,” knowing that press had gathered at the courthouse in anticipation.

“She went to court, got the divorce decree from the judge, and came right back and joined Desi in bed again — thus invalidating the breakup under California law, which had a one-year period banning cohabitation after a provisional decree,” Purdum writes. “Cuddled together, they read the afternoon papers announcing their split. After that, they went back to their Desilu ranch — and Desi started coming home on the weekends.”