Missing at sea, lost in Cyclades. HMS Triumph left Alexandria on 26th December 1941 to land a party of commandos ashore and then patrol the Aegean. Four days later she signalled that the party had been successfully landed at Bireans. She was due to return to pick up the commandos on 9th January but failed to make the rendezvous. Nothing further was heard of the submarine. No axis power claimed her destruction and it is believed that she struck a mine