As a chief of staff in the National Assembly, Jang Tae-jun influences power behind the scenes while pursuing his own ambitions to rise to the top.

Han Jung-Rok is a former national archer and current deliveryman from 2019. He ends up traveling to the past with his first love, Lee Hye-Jin and meets Im Kkeok-Jeong, a famous thief from the Joseon dynasty. Together, they struggle to survive, put their lives at stake for the people they love, and share a strong friendship.

Bae Ta-Mi works as a director for a big web portal company. She is in her late 30's and is quite competitive. With her competitiveness, Bae Ta-Mi enjoys success. The methods she uses to win has her wondering if she is doing the right thing with her life. Has she sacrificed too much of her personal life for success? Park Mo-Gun is a man in his 20's and is a gifted composer. He creates music for video games. Park Mo-Gun meets Bae Ta-Mi at an arcade. He falls in love with her due to her competitive spirit.

Kim Yoo-Wol (Oh Chang-Suk) became an orphan and he was raised by foster parents. He worked extremely hard and passed his CPA exam. He enjoys happy days with his girlfriend Yoon Si-Wol (Yoon So-Yi), but he has a near-death experience. He changes his life and goes under the alias of Oh Tae-Yang. He is dead to Yoon Si-Wol. Meanwhile Yoon Si-Wol, who believes her boyfriend Kim Yoo-Wol is dead, has a difficult time. She begins to work at conglomerate company Yangji Group. There, she meets Oh Tae-Yang.

Min Jae-Hee is a middle aged woman. She is a housewife who has devoted her life to her family, but her family gets destroyed. Min Jae-Hee is furious at the world. Through a mysterious perfume, Min Jae-Hee's appearance suddenly changes to a beautiful young woman. She becomes a model with her new youthful appearance. Min Jae-Hee meets Seo Yi-Do (Shin Sung-Rok). He is a successful fashion designer, but a mean spirited person.

In a mythical land called Arth, the inhabitants of the ancient city of Arthdal and its surrounding regions vie for power as they build a new society.

Dan is an angel. He is also a troublemaker and also an optimist. Yeon-Seo is a ballerina who does not believe in love. Dan then receives a mission. If he succeeds, he can return to Heaven. His mission is to find true love for Yeon-Seo, but Dan soon falls in love with her.

When Lee Jeong-in and Yu Ji-ho meet, something unexpected happens. Or it just may be that spring is in the air -- and anything is possible.