In 1942, under the command of Leslie Bennington, she sank the Italian merchant Citta di Livorno and later the Italian transport Ogaden, but missed the escorting Italian torpedo boat Montanari.
On 11 September 1944 Porpoise took part in Operation Rimau by ferrying 24 Australian commandoes to the island of Merapas, a small island off the coast of Singapore [REF].