How I Met Your Mother Season 4 Episode 21
The Three Days Rule
Ted breaks one of Barney and Marshall's relationship rules, texting a woman he recently met, so the pair play a joke on Ted by pretending to be the woman.
- 4 - 24The LeapMay. 18, 2009
- 4 - 23As Fast as She CanMay. 11, 2009
- 4 - 22Right Place, Right TimeMay. 04, 2009
- 4 - 21The Three Days RuleApr. 27, 2009
- 4 - 20Mosbius DesignsApr. 13, 2009
- 4 - 19MurtaughMar. 30, 2009
- 4 - 18Old King ClancyMar. 23, 2009
- 4 - 17The Front PorchMar. 16, 2009
- 4 - 16Sorry, BroMar. 09, 2009
- 4 - 15The StinsonsMar. 02, 2009
- 4 - 14The PossimpibleFeb. 02, 2009
- 4 - 13Three Days of SnowJan. 19, 2009
- 4 - 12BenefitsJan. 12, 2009
- 4 - 11Little MinnesotaDec. 15, 2008
- 4 - 10The FightDec. 08, 2008
- 4 - 9The Naked ManNov. 24, 2008
- 4 - 8Woooo!Nov. 17, 2008
- 4 - 7Not a Father's DayNov. 10, 2008
- 4 - 6Happily Ever AfterNov. 03, 2008
- 4 - 5Shelter IslandOct. 20, 2008
- 4 - 4InterventionOct. 13, 2008
- 4 - 3I Heart NJOct. 06, 2008
- 4 - 2The Best Burger in New YorkSep. 29, 2008
- 4 - 1Do I Know You?Sep. 22, 2008