With war looming, she was requisitioned by the
Admiralty on 30 August 1939 and converted to serve as an armed merchant cruiser, which involved the fitting of a number of guns. She was straggling behind the convoy with a group of four other armed merchant cruisers and was sighted by , under the command of
Reinhard Hardegen. Work began that December and lasted until July 1944. She was commissioned in August as HMS
Artifex and after carrying out trials was prepared for service in the
Pacific theatre. She sailed to join the
British Pacific Fleet in early 1945, and by March was being deployed out of
Manus in the
Admiralty Islands, supporting the ships of Task Force 57.
Artifex took passage to
Leyte on 19 April to support ships involved in the attacks against the airfields in the
Sakishima-Gunto Islands. She remained here throughout April and much of May, sailing for Manus again on 20 May. She remained here for the rest of the war. On being released from the British Pacific Fleet in September she sailed back to Britain. ==Post-war==