The 21-Day Theory(2025)
The 21-Day Theory Synopsis
Using the 21-Day Theory, a determined woman pursues a wealthy man to prove he's straight—but the truth defies her expectations.
The 21-Day Theory (2025) is a drama series that premiered on January 17, 2025, spanning 1 season and 4 episodes. It stars Narikun Ketprapakorn, Supakorn Saokhor, Pataraphol Wanlopsiri and Dom Hetrakul. Viewers rate it 9.0 out of 10 across 1 ratings.
- First aired:
- 2025-01-17
- Last aired:
- 2025-02-07
- Producers:
- Saithip Montrikun Na Ayudhaya, Vorarit Vaijairanai
The 21-Day Theory (2025) Trailer
Watch the official trailer for The 21-Day Theory before you start streaming.
The 21-Day Theory Cast & Crew
Main cast
Key crew
Executive produced by Saithip Montrikun Na Ayudhaya and Vorarit Vaijairanai.
Explore more Drama shows
The 21-Day Theory Reviews & Ratings
Average viewer score of 9.0/10 from 1 ratings.
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The 21-Day Theory – Frequently Asked Questions
Where can I stream The 21-Day Theory?
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The 21-Day Theory (2025) does not have a confirmed streaming service listed for your region yet. Availability is refreshed regularly, so check back for updates.
How many seasons of The 21-Day Theory are there?
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The 21-Day Theory has 1 season and 4 episodes in total, starting from its premiere on January 17, 2025.
Is The 21-Day Theory still running?
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No. The 21-Day Theory is marked as ended, with the final episode airing on February 7, 2025.
Who is in the cast of The 21-Day Theory?
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The 21-Day Theory (2025) stars Narikun Ketprapakorn, Supakorn Saokhor, Pataraphol Wanlopsiri and Dom Hetrakul. The full cast list with character names is available in the cast section of this page.
Is The 21-Day Theory any good?
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The 21-Day Theory (2025) is rated 9.0 out of 10 from 1 viewer votes, and suits viewers who like drama series. Reviews from viewers are collected further down this page.
Where can I watch the The 21-Day Theory trailer?
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The official The 21-Day Theory trailer is embedded in the trailer section of this page and plays instantly in your browser.