“You know how to whistle, don’t you, Steve? You just put your lips together, and…blow.” With that seductive line, delivered with a steely glare and husky voice, the world was introduced to a screen siren for the ages: Lauren Bacall. The line, later named the 34th-greatest in the history of cinema by the American Film Institute, was delivered in Howard Hawks’ To Have and Have Not, and written by none other than William Faulkner. And the dumbstruck man on the receiving end of the double entendre was Humphrey Bogart who, at 44, had a quarter of a century on this sultry, 19-year-old ingénue. It was the beginning of a beautiful romance—one that would become part of Hollywood lore.

Bacall, who passed away August 12 at 89 after suffering a stroke in her home, leaves behind a rich screen and stage résumé that includes two Tony Awards (for Applause in ’70 and Woman of the Year in ’81), an Academy Award nomination (The Mirror Has Two Faces, ’96), and a number of classic films, including To Have and Have Not, The Big Sleep, and Key Largo. In addition to her stellar body of work, she will always be remembered for being the no-nonsense half of Bogie and Bacall.

After being discovered by the wife of filmmaker Hawks in the pages of Harper’s Bazaar, Betty Joan Perske signed a four-page contract in May 1943, placing her under Hawks’ control for up to seven years at a starting salary of $100 a week. Hawks helped create what would become Bacall’s onscreen persona—tough yet tender, a dame to kill for. He told her to change her name to “Lauren Bacall” (she was Jewish), had his wife update her style from homemaker to movie star, and advised the aspiring actress to rid herself of her Bronx accent by driving out to a deserted spot along Mulholland Drive and reading aloud from the 1942 novel The Robe, to develop a lower, smokier, and—yes—sexier voice.

Bogart and Bacall’s first meeting was in October 1943, when Hawks took the then-18-year-old actress to meet the 43-year-old on the set of his film Passage to Marseille. “There was no clap of thunder,” Bacall later wrote, adding that she found Bogart “slighter than I imagined—5’10½”—wearing his costume of no-shape trousers, cotton shirt, and scarf around neck. Nothing of import was said, but he seemed a friendly man.” Later, when Hawks told his actress he was thinking of casting her opposite Cary Grant or Bogart, she was less than impressed by the latter. “I thought, ‘Cary Grant—terrific! Humphrey Bogart—yucch,’” she later told People.

A couple of weeks before the cameras started rolling on To Have and Have Not, the two co-stars met again on the Warner Bros. lot. Bogart, ever the lady killer, told her he’d been impressed by her screen test and cooed, “We’ll have a lot of fun together.”

But sparks didn’t fly immediately. Bogart was in the midst of his third marriage to Mayo Methot—an unstable alcoholic who once stabbed him in a fit of rage, according to the 1997 biography Bogart. They were dubbed the “Battlin’ Bogarts,” and despite all their troubles, he remained fiercely loyal to their marriage.

All that changed on February 29, 1944. It was the first day of shooting on To Have and Have Not, and Bacall’s first scene in her first film would be one of its most memorable: the hallway entrance, with her glamorous character, “Slim” Browning, purring, “Anybody got a match?” While Bacall seems like a paragon of cool confidence in the final product, she was a nervous wreck on set. She was so nervous, in fact, that she couldn’t hold the cigarette still.

“I used to tremble from nerves so badly that the only way I could hold my head steady was to lower my chin practically to my chest and look up at Bogie,” she later told People. “That was the beginning of The Look. I still get the shakes from time to time.”

The Look, predatory eyes and pursed lips, became her trademark—and was even used as a marketing tool by To Have’s distributor, Warner Bros. The two stars were constantly joking and flirting with each other on set, with Bacall reducing the stoic Bogie to a giggling schoolboy. And then it happened: “He was standing behind me—we were joking as usual—when suddenly he leaned over, put his hand under my chin and kissed me,” she recalled.

From there, the two were attached at the hip, referring to each other by their character names, Slim and Steve (when he wasn’t calling her “Baby”). “They really were smitten with each other,” Joy Barlowe, a Warner’s dancer taken on for the café scenes, said in Bogart. “You could tell by the looks. He always had his hand on her shoulder. And he called her Baby…They were always disappearing. That was when directors told the company, ‘O.K., take a break, be back in 15.’ And the rest of us, we’d be right back there…But they would disappear into one or another of their dressing rooms, and sometimes 15 minutes ran a little longer. But we just thought, Oh, what the heck. And they’d come out looking very happy, a little mussed up, but nothing that you couldn’t fix.”

“Everyone could see their love right there on celluloid,” added their son, Stephen Bogart. “He was the great love of her life, and she his.”

Bogart, however, was still married to Methot, and after she relapsed with alcohol and then promised to get better, he felt it was only fair to give her another chance.To Have and Have Not was a big success, with sellout showings and Jack Warner anointing Bacall as an instant superstar, and so the trio of Hawks, Bogart, and Bacall reunited the following year, 1945, to shoot the crime caper The Big Sleep. Bogart apologized profusely to Bacall and confessed his love to her (again), but he wasn’t ready to leave his wife. “I said I’d have to respect his decision,” Bacall later wrote in her 1978 autobiography, Lauren Bacall by Myself, “but I didn’t have to like it.”

But Bogart and Methot split again eight days into shooting The Big Sleep, only to get back together again after she showed up on his doorstep appearing sober and vowing to clean up her at. Bacall, meanwhile, was a total mess on the set. She was crying so much that an assistant was tasked with giving her ice packs to reduce the swelling. And Bogart was a wreck, too. Hawks at one point advised him to seek psychological counseling to get a handle on his feelings for Bacall. Things came to a head during Christmas weekend, 1945. Methot had fallen off the wagon, and the stress of balancing his loyalty to his wife and love for Bacall weighed heavily on Bogart, so he disappeared into alcohol and went missing from the set for two days. When he emerged from his drunken stupor, his relationship with Methot was kaput. They announced their divorce in February 1945, and on May 21, 1945, he married Bacall in a small ceremony on the farm estate of author Louis Bromfield in Ohio.

“As I glanced at Bogie, I saw tears streaming down his face—his ‘I do’ was strong and clear, though,” wrote Bacall. “As Judge Shettler said, ‘I now pronounce you man and wife,’ Bogie and I turned toward each other—he leaned to kiss me—I shyly turned my cheek—all those eyes watching made me very self-conscious. He said, ‘Hello, Baby.’ I hugged him and was reported to have said, ‘Oh, goody.’ Hard to believe, but maybe I did. Everyone hugged and kissed everyone else and more tears were shed. Bogie said it was when he heard the beautiful words of the ceremony and realized what they meant—what they should mean—that he cried.”

Bogie and Bacall purchased a $160,000 mansion in Holmby Hills, a posh enclave in Los Angeles, and played house. Although they had the occasional spat—he was a homebody who spent a lot of time on his yacht, Santana, and she enjoyed socializing—they both found happiness in each other. In 1949, the couple had a son, Stephen, named after Bogart’s character in To Have and Have Not, and then a daughter, Leslie, three years later. And when Bogart developed esophageal cancer in 1956, the result of his constant smoking and drinking, Bacall was right there by his side—through the removal of his esophagus, chemotherapy, and several other surgical procedures. Bogart passed away on January 14, 1957. He weighed just 80 pounds when he died.

“What it felt like to be so wanted, so adored!” Bacall said of Bogie. “No one had ever felt like that about me. It was all so dramatic, too. Always in the wee small hours when it seemed to Bogie and me that the world was ours—that we were the world. At those times, we were.”