The World's Finest Assassin Gets Reincarnated in Another World as an Aristocrat

Introduction

1.) ENHYPEN Sunoo as Lugh Tuatha Dé - The son of Cian and Essly, Lugh is the designated heir of the House of Tuatha Dé, taught in both the arts of medicine and assassination by his father. He is tasked by the Goddess with the job of killing the Hero after he defeats the Demon Lord as a prophecy revealed that the Hero, drunk on power, would destroy the world himself after defeating the Demon Lord.

2.) Hi-L Soojung as Dia Viecone - Lugh's love interest and childhood friend, Dia first met Lugh as his teacher in the ability to use magic. She is one of the most powerful mages in the world and becomes even more powerful with the help of Lugh and his all-around knowledge of the modern world.

3.) STAYC Seeun as Talt - Lugh's assassination assistant, Talt is a mage saved by Lugh who wholeheartedly entrusts herself to her savior. On the surface, she appears as Lugh's beautiful attendant.

4.) WEEEKLY Zoa as Maha - Lugh's adopted sister, Maha is yet another mage saved by the machinations of Lugh although at that time, he was known by his alias, Illig Balor. She serves as the CEO of Lugh's cosmetics brand while Lugh is absent.

5.) Bigbang G-Dragon as Cian Tuatha Dé - Lugh's father, he is the current head of House Tuatha Dé. A loving father, he is proud of the fact that his son has absorbed so many of his teachings, especially on the occasion where his son broke his family creed to help his loved one, similar to how Cian himself had done the same to help his own significant other.

6.) Sandara Park as Essly Tuatha Dé - Lugh's mother, she is also a noblewoman of House Viecone and is a relative of Dia. She was initially against raising Lugh as an assassin of House Tuatha Dé but was convinced by her husband who promised that he would protect Lugh with all of his power. Essly loves to tease her son and often gets into cooking contests with him after teaching him and eventually discovering he was especially skilled in the culinary arts.

7.) BLACKPINK Jisoo as Goddess -  An entity from the afterlife who offers Lugh the chance to be reborn in another world with his memories intact, but with the condition of killing that world's greatest hero.

8.) BIGBANG T.O.P as Assassin (Lugh's Previous Self)

9.) Fromis_9 Nagyung as Epona Liannenon - a character of the series. According to Goddess, she is the hero who will destroy the world in the future. She is a man on the family register, but she is actually a woman.