TV series

The 21-Day Theory

2025 · 1 season

A slow-burning, emotionally charged drama that keeps you guessing about love and identity.

Created by: Chainarong Tampong
Genres: Drama
Starring: Narikun Ketprapakorn, Supakorn Saokhor, Pataraphol Wanlopsiri

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

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In the UKNo streaming, rental or purchase options known.

Created by: Chainarong Tampong
Genres: Drama
Starring: Narikun Ketprapakorn, Supakorn Saokhor, Pataraphol Wanlopsiri

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How it feels

Written by AI. It can be wrong.

Tone: melancholicstrength 2 of 3
romanticstrength 2 of 3
tensestrength 1 of 3
Pacing: slow-burn, 1 of 4, from slow-burn to relentless
Attention: engaged, 3 of 4, from background-friendly to demanding
Themes: identity
love
deception
class
sexuality
Places: big city
Era: contemporary
Audience: teen
Form: true story
serialised
Content intensity: Gore none
Language mild
Violence none
Sex mild

All scales, 0 to 10

Scales, 0 to 10
Scale	Value	0 to 10
Action	2
Horror	0
Humour	3
Realism	6
Romance	6
Tension	5
Darkness	4
Complexity	5
Emotional weight	7

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Where to watch in the UK

No UK streaming, rental or purchase options are known.

Streaming data from JustWatch.TMDB

Details

Genres: drama
Created by: Chainarong Tampong
Starring: Narikun Ketprapakorn, Supakorn Saokhor, Pataraphol Wanlopsiri, Dom Hetrakul
Cinematography: Paiboon Phupradub
Length: 1 seasons, 4 episodes, 45 min each
Network: ONE 31, Viu
Country: Thailand
Languages: Thai

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The 21-Day Theory

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Where to watch in the UK

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