Open the door and you are a greeted by an amazing display of Baroque art in a brightly lit interior. There are stuccoes by Paolo Corso and Giuseppe Serpotta. Frescoes in the nave and the vault by Tancredi, Borremans and Velasquez. They were severely damaged during WW2 but expertly restored. There is a wood crucifix by Fra’ Umile. Giacomo Besio of the Theatines order built the Chiesa di San Giuseppe dei Teatini at the beginning of the 17th century. It has a large a blue and yellow ceramic dome.