Argala joined ETA V in January 1971. They were a small group that made their ideology very clear. Argala helped militants like Txomin Iturbe and Eustakio Mendizabal build a theory based on Marxist theories, while stressing Basque national values. He spent some time in Paris undertaking organizing tasks and then he went back to Biscay as leader of the Cultural Front. He divided his life between the towns of Eibar and Elgoibar. However, the fact that he was involved in the Cultural Front did not keep him from taking part in the Military Front. On 30 September 1971, he participated in the assault of Banco de Vizcaya together with Eustakio Mendizabal and some other members, getting away with 10 million pesetas.