'Blues' was a British naval undertaking to maintain an invasion threat against the southern part of German-occupied Norway with the object of persuading the Germans not to divert significant forces from Norway to the mainland of Europe in the period soon after 'Overlord' (22/23 June 1944).

Under the command of Rear Admiral R. R. McGrigor, the element of Admiral Sir Henry Moore’s Home Fleet in this undertaking comprised the elderly fleet carrier Furious, heavy cruisers Devonshire and Kent, and light cruiser Bermuda. The Germans did not react in any appreciable manner.