The 21-Day Theory

TV Show90%

The 21-Day Theory

Drama

Using the 21-Day Theory, a determined woman pursues a wealthy man to prove he's straight—but the truth defies her expectations.

Jan 17, 20251 seasons4 episodesEndedTH

Cast spotlight

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Narikun Ketprapakorn

Narikun Ketprapakorn

Pie

Supakorn Saokhor

Supakorn Saokhor

Boss

Pataraphol Wanlopsiri

Pataraphol Wanlopsiri

Euro

Dom Hetrakul

Dom Hetrakul

Barami

Seasons

Season 1

Season 1

4 episodes

Premiered Jan 17, 2025

Episodes

1–4 of 4

Episode 1

Episode 1

Episode 2

Episode 2

Episode 3

Episode 3

Episode 4

Episode 4

Gallery

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Where to watch

No US provider data available from TMDB.

Networks

ONE 31

TH

Viu

TH

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