On Wednesday April 10th 1912, Rose boarded the luxurious RMS Titanic in Southampton, England, at the age of 17 with her mother and her fiancé Cal. The trio were going home to Philadelphia, PA, in America, so Rose and Cal could get married. Rose was, at first, unimpressed with the ship, saying -- "It doesn't look any bigger than the Mauretania." This statement suggests that Rose has been aboard other large ships of the 1912 era. Once on board, she was shown to be fond of artwork; possessing both works by Monet and Picasso. Her relationship with Cal was strained; he scoffed at her interests and controlled her actions. Tired of her repetitive lifestyle and her treatment by people as an ornament, she attempted to commit suicide on the Titanic the night of Friday April 12th by attempting to throw herself off of the stern of the ship. She was stopped, however, by a handsome third-class passenger, an artist named Jack Dawson. He dissuaded her from suicide, commenting how cold the water was: "it hits you like a thousand knives stabbing you all over your body". On the way back over the railing, she slipped and her terrified screams were heard by three of the crew members, who came rushing in an effort to assist her. When they arrived, however, Jack had managed to pull Rose to safety but he fell on top of her, her white face, screaming for help and severe shaking convinced them Jack had tried to rape her. When Cal arrived, he attempted to arrest Jack and even grabbed him calling him "filth". Rose stepped in, claiming she had slipped whilst she had been trying to view the propellers and Jack had saved her. Cal originally wanted to pay Jack $20 ($500 today) for rescuing Rose, but Rose was displeased with this, asking Cal if that was "the going rate for saving the woman [he] love[d]". To pacify Rose, Cal invited Jack to dinner in the first-class dining Saloon. That evening, Cal gifted to Rose the Heart of the Ocean, an inordinately valuable diamond necklace.

Before they could be discovered, Jack and Rose escaped back to the upper decks. Whilst they kissed passionately, they were watched with genial amusement by Murdoch and the crew in the crow's nest. Their escape proved to be just in time, because at that moment the crow's nest crew spotted an iceberg right ahead.Moments later, despite Murdoch's efforts, the ship struck the iceberg, startling Jack and Rose. They then saw the iceberg looming over them as it glanced off the ship. Jack and Rose later overheard the captain and his crew discussing the damage done to the ship, and realised that the situation was serious. Rose decided that her mother should be warned. On their way back to Rose's living quarters, they were met by Lovejoy, who slipped the diamond necklace into Jack's coat. Before Rose could explain the situation to her mother, Cal had Jack searched, and was subsequently found guilty of stealing the diamond. Rose was in disbelief; she didn't realise that Cal had instructed Lovejoy to slip the necklace into Jack's pocket and silently recalled that she never actually witnessed Jack return it to the safe. Jack was arrested and taken to the Master-at-Arms' office. Rose and Cal were left alone in their suite. Cal slapped Rose hard in the face and called her a slut; he had just grabbed her and start to shake her hard when a crew member knocked and entered, telling them thay needed to put on lifejackets and proceed to the boat deck. When told to leave by Cal, he firmly stated that it was "[the] Captain's orders."