At the start of World War I Lurcher and Firedrake were assigned to the 8th Submarine Flotilla under the command of Commodore Roger Keyes, and were based at Parkeston Quay, Harwich.

[6] After the German cruiser SMS Mainz was heavily damaged and disabled, Commodore Goodenough ordered his ships to cease firing on her at 12:55 pm and a rescue operation was undertaken.

Boats from Liverpool were deployed to retrieve those who had abandoned ship while Lurcher positioned alongside Mainz to transfer the crew who remained on board.

Although the operation had been something of a shambles in the mist, the results were clear: Three German light cruisers and a destroyer sunk against no Royal Navy losses.

Commodore Keyes was ordered to send eight submarines and his two command destroyers, Firedrake and Lurcher, to take stations off the island of Terschelling to catch the German ships should they turn west into the English Channel.

Lurcher sailed from Harwich on 30 May in company with HM Submarines E31, E53 and D6 to patrol positions between Southwold and the Dutch coast,[9] but were not involved in the Battle of Jutland, which occurred further to the east.

[10][11] At about noon on 6 July 1918 a squadron of five German seaplanes returning from a daylight raid on Lowestoft and Walmer came across C25 on the surface 15 miles (24 km) east of Orford Ness.