Woo Do-hwan (Netflix)

For Woo Do-hwan, portraying the main character in Netflix's new romantic comedy series "Mr. Plankton" was far from purely romantic or comedic.

The life of Woo's character Hae-jo, who was born through in vitro fertilization, spirals into turmoil from the age of 8 when it is discovered he was an unintended product of a sperm mix-up, and that the man he believes to be his father is not actually his biological father.

The discovery tears the family apart as the mother dies and his once-loving father turns distant and unresponsive.

Stripped of familial warmth, Hae-jo sets out to carve a path of his own, only to be diagnosed with a terminal illness -- likely inherited genetically -- which prompts him to find his true biological father before it is too late.

Woo, who gained recognition for his lead role in Netflix series "Bloodhounds" and his supporting role in star-studded crime film "Master," for which he won the award for best new actor at the 54th Baeksang Arts Awards, shared that Hae-jo’s sense of profound loneliness drew him to take part in this project.

"The character has endured such deep wounds -- betrayed and abandoned by someone he loved -- which made him appear incredibly lonely to me. I feel one of the traits people associate most with me is that of a poignant child marked by a deep, sad loneliness just like Hae-jo. I wanted to portray the character like this while I still had the youthful essence to do him justice," Woo said during an interview in Jongno, Seoul, Wednesday.

Beyond the emotional depth, Woo says Hae-jo’s unrestrained nature captivated him.

"Hae-jo seemed free-spirited, unpredictable and unrestrained," Woo assessed.

"Having to go to school, serve in the military and work leaves little time to live freely, so I found myself forgetting what freedom feels like -- a life where you don’t care about others’ opinions. But Hae-jo is a character who lives without worrying about others," he said.

Woo also found Hae-jo's way of life intriguing, especially as he noticed changes in himself as time passed.

"I wondered how I might change after a year or two if I kept meeting more people and working," reflected Woo.

"Perhaps I’d gradually forget what it means to (not care about others’ opinions), and I’d learn to compromise more with life. But Hae-jo is someone who doesn’t compromise, and that made me really want to try taking on this role."

“Mr. Plankton” stars Lee Yu-mi (left) and Woo Do-hwan. (Netflix)

Eventually, playing the role of Hae-jo prompted Woo to reconsider his own life choices, particularly his disciplined approach to living.

"While working on this project, I was living in a rigid, highly disciplined way, much like Geon-woo from 'Bloodhounds.' But after stepping into the role, I started to think, 'Maybe living this way isn’t so bad,'" he said.

"Before meeting Hae-jo, I was set on living my life like Geon-woo forever. I’m still conflicted. If you ask me which direction I’d prefer to live, it’s hard to say."

Director Hong Jong-chan described "Mr. Plankton" as a meditation on human worth. During a Nov. 4 press conference, Hong explained, "Plankton live in the ocean and are so small that they're often invisible, yet they play a pivotal role in producing the oxygen that nurtures life on our planet. Their significance cannot be overstated, and I sought to convey that we are all like plankton."

Woo echoed the sentiment.

"Through this project, I came to feel the value of existence. (The series is) noisy, unpredictable and full of words that don’t always align with the heart, yet it undeniably exudes warmth. ... That’s why I consider it a heartwarming drama."

All 10 episodes of "Mr. Plankton" are now streaming on Netflix.