The church is wedged into the vast monumental complex that originally included the Convent and the Jesuit Schools. Founded in 1602 and consecrated in 1620, it has an unfinished façade with four fluted pilasters of giant order framing a Serlian window. The façade is classicist, while the bell tower is Baroque, the style that predominates inside in the rich decoration and spaciousness of the single nave, punctuated by side chapels. Of particular interest is the altar of the Virgin, the last on the left, with two panels depicting Martirio and Gloria di Sant'Orsola (1652) by Luigi Miradori, known as Il Genovesino.

The central niche of the altar houses an elegant wooden sculpture of the Immacolata  (c. 1686) attributable to the Milanese sculptor Giuseppe Rusnati, while the wooden angels at the top of the altarpiece are by Giacomo Bertesi (1643-1710), who also created the spectacular wooden altarpiece of the high altar, which frames the altarpiece by Gervasio Gatti depicting Santi Marcellino e Pietro che impartiscono il battesimo a Paolina (1604).
The presbytery celebrates the patron saints of the church, who are also depicted in the two side paintings (Santi Marcellino e Pietro che soccorrono i Cremonesi in battaglia and Il trasporto delle reliquie), by Angelo Massarotti (1654-1723). Rococo is also documented at the highest level with the high altar and that of St. Francis, the only marble altars in the church, both by the architect G. B. Zaist (1700-1757).