Before Oceanic 815
Penelope first met Desmond at Moriah Vineyard, an abbey famous for the wine it produces. Desmond helped her load cases of wine her father bought and Penelope offered him a ride. The two were involved in a romantic relationship for two years before Penelope finally moved into Desmond's flat because Desmond was too proud to move into her more expensive flat. Even though she is the daughter of a very wealthy businessman, Desmond's more modest means of living weren't an issue in her mind. She loved Desmond unequivocally, but Desmond was bothered by his supposed inability to look after her. In addition to Desmond's self-doubt, her father felt Desmond wasn't worthy of marrying Penelope and made his opinion pointedly clear to Desmond. Desmond used these excuses to break up with her, but Penelope believed he was doing it because he was a coward.
Before Desmond left for military prison, Penelope wrote a letter of encouragement to him and hid it in the one place he would turn to in a moment of great desperation - a novel he would only read right before he would die. In it she told him she would always love him and would wait for him. During Desmond's incarceration, Penelope believed he had forsaken her as she never received any letters from him. She moved on and developed a relationship with another man. In truth, her father had prevented Desmond's correspondence from reaching her, believing it was best that she moved on and never communicated with Desmond ever again.
After Desmond finished his prison sentence, but never contacted her, Penelope used her wealth to track him down to Los Angeles. Upon finding him, she discovered he hadn't read his novel and, subsequently, her letter. She revealed that she and her fiancé had yet to set a date for their wedding. However, she still harbored feelings for Desmond and wanted him to come back to her. She was told by Desmond that it would be a year before that could happen, as he wanted to win her father's solo sailing race and get back his honor.
Three years after Desmond's departure on Charles Widmore's solo sailing race and subsequent disappearance, Penelope received a phone call from a listening post that detected an electromagnetic anamoly. She was told they had found "it."
- 2x23 - Live Together, Die Alone (1)
- 2x24 - Live Together, Die Alone (2)
- 3x08 - Flashes Before Your Eyes
- 3x17 - Catch-22
- 3x23 - Through the Looking Glass (2)
- 4x05 - The Constant
- 4x14 - There's No Place Like Home (3)
- 5x01 - Because You Left
- 5x02 - The Lie
- 5x03 - Jughead
- 5x12 - Dead Is Dead
- 5x14 - The Variable
- 6x11 - Happily Ever After
- 6x18 - The End (2)
- Information is shown in chronological order.
- 3x17 - Catch-22: Meets Desmond for the first time.
- 3x08 - Flashes Before Your Eyes: Moves into Desmond's flat, but Desmond ends their relationship shortly after.
- 2x24 - Live Together, Die Alone (2): In flashback, Penelope finds Desmond at a stadium and talks with him. After the Swan's fail-safe device is activated, she is contacted by a listening post and told they've found it.
- The Photograph: In season two's "Orientation", Desmond's photograph of himself and Penelope is seen by Jack. However, the woman in the photo is not Sonya Walger as she had not yet been cast for the role of Penelope. The photo was digitally altered to include her as of "Live Together, Die Alone."