Series · 2022 · Drama
A playful rivalry turns into something more when a cocky senior dares his classmate to win the school’s top celebrity’s heart in just 21 days.
1 season · 4 episodes

Episode 01
Episode 1
Q meets X and is challenged to beat him in 21 days—sparking rivalry and unexpected bonds.

Episode 02
Episode 2
After X’s injury, Q tends to him closely, giving them a chance to see each other differently.

Episode 03
Episode 3
As their days together grow, Q’s feelings shift, and mutual understanding slowly deepens.

Episode 04
Episode 4
At a turning point, Q and X must face whether the “21-day theory” will define their future.
based on 8 votes
A playful rivalry turns into something more when a cocky senior dares his classmate to win the school’s top celebrity’s heart in just 21 days.
7 principal cast
21 Days Theory is available to stream on Flicksy via 6 verified sources, aggregated from publicly available embed providers. The drama from Choi Sittichai Chutsiri has 1 season and 4 total episodes, rated 7.0/10 by 8 viewers.
21 Days Theory has 1 season with 4 episodes in total.
21 Days Theory has ended and is no longer in production.
21 Days Theory airs on YouTube.
21 Days Theory first aired on August 7, 2022.
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