Season 1 of HeartBeat premiered on June 26, 2023.

Seon Woohyeol is a vampire who wants to become a human but ended up becoming half-human when he woke up a day before completing his 100 years of sleep. Meanwhile, Joo Inhae is a modern lady who shows no compassion about him and only wanted to survive. Will they find love and learn to care for each other now that fate brought them together?