He started his professional career by impersonating Greek public figures, mainly sports people (e.g. famous sportscaster Giannis Diakogiannis and Filippas Sirigos) and politicians (prime ministers Konstantinos Karamanlis and Andreas Papandreou) on radio satiric shows on FM Radio station "Athens 98.4".
The name of his show had the -completely- random title, "The conspirators of the night, in the conspiracy of the patsas" (Greek: Οι συνωμότες της νύχτας, στη συνωμοσία του πατσά), in which his co-presenator was, the later well-known TV presenter, Nikos Evaggelatos.
Since then he has been on many Greek channels, and afterwards started to impersonate actors, singers and journalists as well, and changed the form of his shows.
It is said that sometimes when a Greek celebrity called a restaurant or a hotel to book a seat, the persons on the other end of the line thought it was Mitsikostas making pranks.
Such persons include Giorgos Georgiou, Kostas Karamanlis, Vassilios Tsiartas, Giorgos Karagounis, Christoforos Papakaliatis, Terence Quick, Evangelos Marinakis, Nikos Alefantos, Fotini Pipili, Konstantinos Mitsotakis, Dora Bakoyannis, Margaret Chant-Papandreou, Dušan Bajević, Kostas Kazakos, Sakis Rouvas, Vasilis Leventis, Antonios Nikopolidis, Theodoros Roussopoulos, Sotiris Ninis, Alexis Papahelas, Constantinos Christoforou, Dimitris Ververelis, Adonis Georgiadis, Anna Vissi, Lakis Lazopoulos, Kyriakos Mitsotakis, Andreas Mikroutsikos, George Papandreou, Nikos Chatzinikolaou, Alexis Kougias and Stefanos Kasselakis.