This vast, castellated church has an extraordinary rear entrance, with a curved double flight of marble steps leading up from the piazza. However, it is best entered from the side street, Vico San Domenico. Here, the porticoed entrance dates from the late 13th century, when the church was built, incorporating the pre-existing church of Sant'Angelo a Morfisa. The chapels include some fine works of art: 13th-century marble tombstones (the first chapel on the right); 14th-century frescoes by the great and unjustly neglected Roman artist Pietro Cavallino (second on the right); and a couple of paintings by Mattia Preti (fourth on the right). The Neapolitan headquarters of the Dominican order, the monastery played host to the hermeticist philosopher Giordano Bruno (burnt at the stake for heresy in Rome in 1600), who studied here, and St Thomas Aquinas, to whom the sixth chapel on the right is dedicated. The figure of Jesus in the 13th-century Crucifixion over the altar is said to have spoken to Thomas, offering him anything he wanted in return for the nice things the saint had written about Him. To this, Thomas replied, 'Nothing, if not You'. The luminous sacristy has a fine ceiling fresco by Francesco Solimena and a bizarre set of coffins; their contents include the decapitated body of a victim of the barons' conspiracy of 1486.