From a young age he was involved in insurance and commercial enterprises; he was cleverly elected president of the Greek insurers, vice-president of the Athens Commercial Association, member of various associations and bodies, and built a social profile.

In 1929 he took part in the municipal elections in the same combination as Kostas Kotzias (also of Tekton). In 1934 he was elected for the first time as a councillor. When Kotzias took over as capital city commander, Plytas succeeded him as mayor. He produced important work. In 1941, with the entry of the Germans, as a committee member of the city of Athens and other communities of the diaspora, he handed it over to the Germans. But he refused to cooperate and the Tsolakoglou government removed him from office and the city council was dissolved. Plytas was one of the founders of a spy organization“Elefthera Megalos Ellas“, for which reason the Italians confiscated his property. During his mayoralty, the Museum of Modern Times was founded and the second floor of the Athens City Hall was erected.