''Poikkal Kuthirai'' is a hilarious depiction of how Sambandam (Vaali) — who bets on each and every small thing and wins — and Indu (Ramakrishnan) enter into a bet at a saloon owned by Muthu (Ravindar). The bet is that Indu will win Sambadam's daughter Janaki's (Viji) heart and marry her. If Indhu is successful in his mission, Sambandam will shave half of his moustache for their marriage. If he fails, Indhu will shave his head. Who wins the bet is the film's narrative.