In their final scenes, shot in Enfield, North London, Gary apparently jilts Dawn on their wedding day after he learns she's cheated on him with Albert Square bad boy Phil Mitchell.
But realising Gary's about to sail out of her life forever, Dawn rushes to the canal with Heather, played by Cheryl Fergison and Shirley - aka Linda Henry - and begs for another chance.
Kara has been looking forward to lensing her exit since she read the script, and was particularly pleased to learn her character wasn't being killed off. "I think I'd refuse to do the dying scene," she says.
"I'd like to believe that Dawn will be out there somewhere, because she's been a big part of my life for so long," adds the 25-year-old beauty, who has been with the BBC show since September 2005. Ricky, who plays her on-screen love interest, leaves after almost nine years with the programme.