It is decorated with the monumental stucco alabaster Rococo sculpture Fall of the Angels (1782) by sculptor Karl Georg Merville.
The centerpiece of the high altar is Maria Candia, a Byzantine icon of the Virgin Mary, belonging to the Cretan School of hagiography and named after the former capital (now Heraklion), displayed as being carried by two archangels.
The recently rediscovered frescoes from the early 15th century attest to the high quality of the art of painting in Vienna in those times.
One of those who attended the "festive funerary honors" was theater director Emanuel Schikaneder whose libretto was used by Mozart for The Magic Flute.
Above the entrance, on top of the pediment, resting on Doric columns by Antonio Beduzzi, stands a group with winged angels and St. Michael slaying Lucifer (1725).
Aristocrats were able to access their family crypts through marble slabs marked with their coats of arms in the church floor.
Hundreds of mummified corpses, some still in burial finery or with a wig, are on display, some in open coffins, adorned with flowers or skulls, others decorated with Baroque paintings or with vanitas symbols.
The excavation site was made permanently accessible to the public in 1991; the design of the presentation is by architect Hans Hollein.