D’Artagnan kann an den Wettkämpfen um die Mitgliedschaft bei den Musketieren teilnehmen. Aber seinem Gegner Widimer ist jeder nur erdenkliche Trick recht, um ihn auszuschalten. Doch die Freunde Athos, Portos und Aramis greifen ein und besiegen Widimer. D’Artagnan gewinnt und soll zum Musketier ernannt werden. Kardinal Richelieu und Widimer erheben Einspruch, weil D’Artagnan angeblich bei den Wettkämpfen geholfen wurde.
As Dogtanian practises his swordsmanship, Aramis rides up to tell him that there is a vacant place in the Musketeers and Dogtanian must compete against other hopefuls to win it. Treville confesses that he wants Dogtanian to win but strictly forbids the Three Muskehounds to help him. Widimer enters one of his Guards in the hope that he will enter the Muskehounds and spy on them. The competitors run a horse race, in which the Guards' candidate cheats but some trickery by Pip and a parrot gets Dogtanian and Sandy back in the running, and swim a river, Pip again sabotaging the other candidates. Now only Dogtanian and Widimer's man are left to undertake the final task: making their way through the forest at night to retrieve a hat, avoiding various traps. The Three Muskehounds find Widimer at the finishing post and drive him away, while Pip and Sandy get rid of the Cardinal's Guard. This makes Dogtanian the winner, but Richelieu objects on the grounds of outside assitance and Dogtanian's
D’Artagnan passe avec succès tous les tests pour devenir mousquetaire. Il est l’un des deux meilleurs candidats et l’autre finaliste est un des hommes du cardinal. Mais son capitaine, qui veut empêcher D’Artagnan d’accéder à ce rang, n’a pas dit son dernier mot...
Dartacão supera as provas com êxito e fica em primeiro lugar entre os candidatos. O outro aspirante é um homem de Widimer que usa todos os truques para derrotar Dartacão. Os Três Moscãoteiros envolvem-se e lutam com Widimer. Quando Dartacão se apresenta perante o rei para ser proclamado Moscãoteiro, Richeleão levanta objecções contra ele e por isso acaba por ser desclassificado.