Choi Ban Do and Ma Jin Joo are both 38-years-old and a married couple. Choi Ban Do has been burdened with being the breadwinner and Ma Jin Joo is a housewife with low self-esteem. Even though they loved each other when they married, they now hate each other. They both regret marrying at such a young age. The couple travel through time and find themselves as 20-year-old university students, when they met for the first time.

At a difficult place in his marriage and career, a middle-aged man gets a shot at a do-over when he's transformed back into his 18-year-old body.

The story of Park Jin Sung who owns a late-night snack restaurant.

Adapted from the webtoon series "Welcome", this TV series tells the story of graphic designer Kim Sol Ah who brings home a cat, unaware that the animal can turn into a human being.

With the Korean peninsula under threat from a devastating volcanic eruption, unlikely allies carry out a secret mission to prevent the disaster.