Theory of Love (2019) is one of the first that comes to mind when Thai BL series are mentioned. To put it without exaggeration, it is one of the first and best examples of this genre. The series describes not only love, but also emotional confusion and the process of self-discovery. A cult youth series. Especially suitable for those who are just starting to watch boys’ love. Imagine, you want to watch the best among hundreds of BLs and you don’t know where to start. You can start with this series.
Despite the long years that have passed, I can say that Theory of Love is still at the top. It is one of my favorites among youth-themed BL series. Also, the chemistry and harmony of the “GunOff” duo in this early period BL series is worth watching as always. Another importance of this series is that it is one of the productions that made the BL genre globally recognized. “GunOff” gives life to unforgettable characters. You should take the series into your watch list, it will offer you a top-level drama quality. Also, you should watch Not Me (2021), which is one of the best BLs played by the legendary couple. Again, you can also take Burnout Syndrome (2025-2026) into your watch list. Now let’s move on to the details.
🏳️🌈 Curator BL Recommendations: Best BL series (Thai, South Korean, Japanese, Taiwanese)
Theory of Love (2019) Plot and Summary
Third’s Love: A One-Sided Struggle
Third is a talented and emotional student studying in the film department. He has been harboring a secret love for years for his best friend and roommate Khai. Third does his best to win Khai’s attention; he listens to his problems, stays by his side, and even compromises himself. However, although Khai is aware of this interest of Third, he constantly pushes him into the background. By displaying his relationships with women, he practically tries to prove that he is not gay. This situation wears Third down. In the face of the indifference and insensitivity of the person he loves, he finally gives up.
Third wants to get rid of this big burden in his heart and decides to put his feelings for Khai aside. He takes someone new into his life. This new relationship is like an escape for him; it is a step to get away from the emotional confusion he experienced with Khai, to heal his wounds. But this change affects Khai unexpectedly.
When Khai realizes that Third no longer acts towards him like before, he starts to confront the feelings he suppressed inside. The fear of losing his friend and the possibility of him being happy with someone else moves Khai into action.
Khai now wants to regain his place in Third’s life. However, Third is cautious this time. Having his feelings constantly ignored has deeply wounded him. It is not easy to trust Khai. The relationship between them bears the traces of a broken past. At this point, the series offers an intense transition to the audience in an emotional sense. Khai’s regrets, Third’s internal conflicts, and the two of them trying to get close again is one of the strongest narrative points of the series. You will focus here as well.
Psychological development: With Third setting a distance, Khai experiences living without him for the first time. Third’s absence causes Khai to understand his own feelings. While jealousy, longing, and regret intertwine, Khai’s love for Third turns into a truth he slowly realizes. However, Third is no longer someone who forgives as easily as before; he has learned to protect his feelings. In future episodes, Khai finally explicitly expresses his true feelings to Third. Third, on the other hand, takes a step without forgetting the heartbreaks of the past, but believing that a new beginning is possible. Of course, most of the healing themes that we express as “cliché” nowadays, traumas coming from the past, exist here as well.
Side Characters and Other Love Stories
Theory of Love does not only focus on Third and Khai’s love. It has sub-stories as well.. There is another love story developing slowly and unable to be confessed between Two and Un. These two characters’ feelings born from friendship but hard to explain bring a sweet and fragile side story to the series. Even if sub-stories stay a bit in the background, they support the main story.
Also, while watching Bone’s love for his teacher, you will experience a different tension. This relationship is both forbidden and emotionally complex. This sub-story handled through a student-teacher relationship increases the emotional diversity in the series. If you like multi-layered BL stories, the series is just for you.
Series Review and Commentary
The series is one of the first examples of that perfect form of Thai BL series. University romance always takes place on a bright campus. I have not always liked overly filtered faces, smooth bodies, and a university atmosphere far from seriousness. But the actor performance, chemistry, and energy are completely in the vibe of a youth series. Neither less nor more. Especially Third’s internal conflicts are reflected very well. The characters are realistic.
However, the basic structure of the series carries similarities with many BL productions. Though the subject of BL series is limited, we already know this. Here as well, there are those famous clichés like class difference, suppressed feelings, relationships turning from friendship to love. Despite this, “Theory of Love” is among the productions that deserve to be watched in terms of character development and internal journeys. The answer to the question of whether the series is worth watching will be: Yes.
Theory of Love Series Information
The story handles the relationships woven with friendship, jealousy, and secret loves of close friends studying at the film faculty. The series will convey to you the transformation of love from theory to practice, that is, the difference between “understanding loving” and “living love” through characters. Friendship will turn over time into an emotional journey where hidden feelings surface. Third and Khai’s story is not just a love narrative, but also a self-realization and a development story.
Original Name: The number of episodes of this legendary production whose original name is ทฤษฎีจีบเธอ: 12. Screenplay: O2 Production, novel adaptation, author: JittiRain. Definitely look at this list too, I recommend it. Where to watch: You can watch it on GMMTV, Viki. If you want more fan comments and a bit of fan service-focused review, you can look at mydramalist. That’s all from me.
Cast and Characters
Third (Gun Atthaphan Phunsawat) is a complex, emotional, and empathy-loaded character in his inner world. He lives love mostly through sacrificing himself, which makes him a fragile but deep figure. Khai (Off Jumpol Adulkittiporn), on the other hand, is an extroverted, charismatic person who is incompetent at expressing his feelings. When he encounters Third’s silent love, he will enter an emotional maturation process. What the characters in the series experience is not just love, but a story of personal development and growth.
Gun Atthaphan Phunsawat (Third) A quiet, emotional, and introverted film student. His secret love for Khai is the biggest conflict shaping his inner world.
Off Jumpol Adulkittiporn (Khai) A charismatic, extroverted, but emotionally immature character. Thanks to Third’s patience and love, he learns to understand his own feelings.
