The movie stars' legendary romance began onscreen and carried over into real life until Bogart's untimely death.

Film stars Humphrey Bogart and Lauren Bacall shared an iconic romance and a happy, albeit short-lived, marriage. They achieved this despite a 25-year age difference, a track record of failed marriages on his part, and her decision to put her career on hold in order to focus on their relationship. No matter the bumps along the way, Bacall was right when she wrote in her memoir, "No one has written a romance better than we lived it."

Bacall admits there was 'no lightning bolt' when she first met Bogart

When she first arrived in Hollywood, 19-year-old Bacall wasn't a big fan of movie star  Bogart. At one point, director Howard Hawks told her he was thinking of putting her in a movie with either Bogart or Cary Grant. Her reaction: "I thought, 'Cary Grant — terrific! Humphrey Bogart — yucch.'"

Hawks introduced Bacall to a 43-year-old Bogart in 1943. "There was no clap of thunder, no lightning bolt," she later wrote about the encounter. However, she was excited when Hawks cast her in her first role opposite Bogart in To Have and Have Not. A few weeks before production started, Bogart told her, "We'll have a lot of fun together."

Fear and nerves had Bacall trembling on her first day of shooting. But Bogart helped her relax, which she appreciated (she also learned to tuck her chin down to hide her shaking, meaning she had to look up at Bogart — an action that became famous as "The Look"). The two developed a joking rapport as the shoot continued, with observers noting that Bogart became almost "giggly" around his co-star.

Lauren Bacall and Humphrey Bogart ride bicycles while on the set of the film 'Key Largo'

Lauren Bacall and Humphrey Bogart ride bicycles while on the set of the film 'Key Largo' in Hollywood, California in 1948.

The director of 'To Have and Have Not' changed the original ending show off their undeniable chemistry

In an unusual step for a Hollywood movie, To Have and Have Not was shot in order. This provided a showcase for the developing connection between Bogart and Bacall, which was evident in the scene where she delivers the famous line, "You know how to whistle, don't you, Steve? You just put your lips together and blow."

The film was supposed to have Bogart's character romance another woman. But director Hawks saw how the two were interacting on film and the screenplay was changed so Bogart's character ended up with Bacall's. As Bacall noted in 2007, "Chemistry — you can't beat chemistry."

Three weeks into filming, Bogart was in Bacall's dressing room at the end of the day, talking and laughing. He then leaned in to kiss her. Next, he asked for her phone number, which she wrote on the back of a matchbook. In 1997, Bacall told Parade magazine, "From then on I would get phone calls, occasionally at 3 a.m. My mother used to say, 'Where do you think you're going so early in the morning? That man, he's a married man!'"

Despite having feelings for Bacall, Bogart remained married to his third wife

Bogart had been married to his third wife, actress Mayo Methot, since 1938. The couple's heavy drinking and arguments had resulted in their being nicknamed "the battling Bogarts." Fights could be so destructive that a carpenter was reportedly on call to handle repairs. In 1942, Methot had become violently enraged and stabbed Bogart.

Being married meant Bogart had to see Bacall in secret. Their meetings took place in cars parked on dimly lit streets, at a golf club near the studio, and during breaks in shooting. They called each other "Slim" and "Steve," the nicknames of their characters in To Have and Have Not.

Filming on To Have and Have Not ended on May 10, 1944. Shortly afterward, Bogart sent Bacall a note that said in part, "I know what was meant by 'To say goodbye is to die a little' — because when I walked away from you that last time and saw you standing there so darling I did die a little in my heart." Though they met over the summer, Bogart felt a duty to stay in his unhappy marriage with his alcoholic wife.

Lauren Bacall smoking a cigarette and leaning on the shoulder of  Humphrey Bogart on the set of the film 'Key Largo.'

Lauren Bacall smoking a cigarette and leaning on the shoulder of Humphrey Bogart on the set of the film 'Key Largo.'

They reunited for 'The Big Sleep,' and their connection was stronger than ever

In addition to Bogart's wife and her mother's disapproval of the relationship, Bacall had to deal with Hawks. The director, who'd likely been interested in romancing Bacall himself (though he was also married), had insisted Bogart had no real feelings for her. He'd also threatened to sell her contract to a lesser studio. Bogart had stood up to Hawks, to the point that the head of the studio had to be called in, but Bacall was still worried.

The success of To Have and Have Not led to Bogart and Bacall reuniting to make The Big Sleep in fall 1944. But Bogart told Bacall that his wife had promised to stop drinking and he wanted to give her the opportunity to do so. In her memoir, Bacall wrote, "I said I’d have to respect his decision, but I didn’t have to like it."

Yet the chemistry and connection between Bogart and Bacall was still there. Soon Bogart left his wife — but then he returned to Methot. His vacillation left Bacall's eyes so puffy from crying they needed to be iced down to be presentable in front of the cameras. During a period of reconciliation with his wife, Bogart called Bacall at three in the morning. Methot then jumped on the line to yell, "Listen, you Jewish b***h, who’s going to wash his socks?"

Bogart and Bacall married 11 days after his divorce from Methot

By the end of 1944, Bogart had come to a final decision. He hated having to end his marriage, to the point that he missed work and disrupted the filming schedule (which was unusual for him). But, after a binge at Christmas, his marriage to Methot was finally over.

Bogart got divorced on May 10, 1945. On May 21, when he was 45 and Bacall was 20, they wed at a friend's Ohio farm. They were addressed as "Humphrey" and "Betty Joan" (Bacall's name had been Betty Joan Bacal before she got to Hollywood) during the service. Bogart cried during their vows and afterward greeted Bacall with a "Hello, Baby," another nickname he'd given her. She reportedly said, "Oh, goody" in reply.

Son Stephen (named for Bogart's character in the first film they made together) arrived in 1949, followed by daughter Leslie in 1952. And though they clashed over some things, like the amount of time Bogart spent on his boat, they were happy together. Bacall later noted, "When Bogie and I were married, the Hollywood gloom set shook their collective heads and moaned, 'It won't last.' We knew better. What the catastrophe-anticipators didn't consider was that the Bogarts were in love."

Lauren Bacall and Humphrey Bogart with their son, Steve

Lauren Bacall and Humphrey Bogart with their son, Steve

Bacall put her career aside to raise their family

Bogart and Bacall would work on two more films together: Dark Passage (1947) and Key Largo (1948). However, Bacall's career was no longer her main focus. "Bogie was an old-fashioned man," Bacall told an interviewer in 1979. "He kidded that a woman’s place was in the home, but he was only half kidding. He had divorced three actresses and was convinced that a career and marriage don't mix."

Bogart proudly stated, "She's my wife, so she stays home and takes care of me." And Bacall made sacrifices such as accompanying Bogart on location so he could shoot The African Queen (1951) with Katharine Hepburn. The role resulted in his only Academy Award for Best Actor, but the trip required Bacall to leave their young son behind.

Yet Bacall had no regrets about her decision. She once told The Guardian, "If I'd had just my career, I would have missed out on Bogie, on children, on the very substance of life." And, as she said in another interview, "[T]hank God I did put our marriage first, because it didn't last too long."

Bogart died 11 years into their marriage

Bogart was diagnosed with cancer of the esophagus in 1956. He went through surgery, but remained very ill, with Bacall taking care of him. On January 14, 1957, he died and Bacall became a widow at 32. "Bogie's death was devastating, but I had to focus on my two young children. So I had something kind of constructive to think of," she told People in 1981.

Bacall would have a short-lived engagement to Frank Sinatra (an unauthorized biography of the singer stated their relationship started during Bogart's illness; according to Bacall they'd only been friends at the time). She was married to fellow actor Jason Robards in the 1960s. They had a son, but Robards' alcoholism was difficult to live with and ultimately contributed to the end of their marriage.

By moving to New York and appearing on Broadway, Bacall revamped her career while continuing to make movies. She was also aware that her life remained tied to Bogart's, telling Vanity Fair in 2011, "My obit is going to be full of Bogart, I'm sure." Yet she appreciated the good fortune she'd had to meet and be with her first husband, once saying, "I was so lucky when I was young. What happened to me then sometimes happens to people when they’re older. And sometimes never happens. So I feel lucky that I had it at all."