When Willem Key died in 1568, Adriaen Thomasz took over his workshop. Although he had converted to Calvinism he did not leave Antwerp after the Fall of Antwerp in 1585 when the Calvinist government of Antwerp was overthrown by Spanish forces led by Alessandro Farnese. He received pupils in his workshop in 1582, 1588 and 1589. He received commissions from the leader of the Dutch Revolt William of Orange and the socio-economic elite of Antwerp. He is last mentioned in a document in 1589. It is not clear whether he died soon after or left Antwerp because of his Calvinist opinions.