When two men find their lives derailed, they meet challenges that force them to face a fierce battle to protect their loved ones.

Sangtae and his teenage daughter Doyeon are constantly arguing and haven't had a genuine conversation in years. When their souls are switched by a magical force for seven days, they must learn to tackle the awkward and unfamiliar situation in each other's shoes.

Along with his young son, Ji-ho, Woo-jin misses his wife Soo-a, who died after promising to return a year later with the rainy season. Miraculously, they reunite with Soo-a when the rainy season comes around, but she has no memory of her husband and son whom she dearly loved.

When a carefree woman learns that her closeted friend is gay, the two form an inseparable bond and find comfort in each other's company.

Kim Dok-ja, an ordinary man in his 20s, is the only reader of an obscure web novel titled "Three Ways to Survive the Apocalypse". After having read the last chapter, the novel suddenly becomes reality, and its omnipotent hero Yu Jung-hyeok appears before Kim. As the only person who knows how to survive in this world, Kim and his companions strive to save the world by writing his own, new ending.