Twenty: Love Shuffle

Four couples, all nineteen and about to turn twenty, enter a partner-swap reality show called Twenty. One of the eight is Han-byul, heir to Kings Group, which she has kept to herself. She has been with Kang Jun-hwan and has given him everything, down to her own status. He has betrayed her, gaslighted her, and used her as his personal cash machine. Sun-woo, a swimming star known as the nation's first love, is brought onto the show as a wild card. He was in an accident and has not spoken since, and he has kept everyone at a distance. On the show he begins to warm to Han-byul, the only person he has let near him since the accident.