A simple and elegant portal leads into the vast interior; it has a single nave covered by a barrel vault, supported by pillars against the walls.  At the Baroque main altar, with architectural and wooden sculptures, is a valuable painting by Giacinto Boccanera Leonessa, dated 1723 and depicting the Madonna holding a monstrance of the Blessed Ruggero, St. Felix, St. Rita and St. Pius V.

Two large niches on the left wall preserve sixteenth century frescoes, one a Crucifixion, and the other a Madonna and Child Enthroned with St. Roch and St. Ambrose. There is also an interesting series of fifteenth century frescoes of the Foligno school, depicting with excellent workmanship the Madonna and Child and another Madonna and Child with Saints. Also preserved there is a large cross inlaid with mother of pearl, some modest eighteenth-century paintings and a painting of the Baptism of Christ from 1957.

The church is named after the patron Felice, who lived and preached in his hometown at the time of the emperors Diocletian and Maximian. In order to crack down on the spread of Christianity, they sent the prefect to Martana Tarquinio, who found Felice and invited him to apostasy. Failing to convince him, he condemned him to be burned on the grill. But Felice came out unscathed from this ordeal and then was beheaded in the forum by the executioner Sevibo. At night the Christians stole the body of the martyr and buried him in the place where the church dedicated to him was built.