It was adapted as an interim long-range and night fighter, pending the availability of the Beaufighter. It was one of the first British aircraft to have all-metal stressed-skin construction, to utilise retractable landing gear, flaps, powered gun turret and variable pitch propellers.
The Blenheim Mk I outshone most biplane fighters in the late 1930s but stood little chance against the German Messerschmitt Bf 109 during daylight operations, though it proved successful as a night fighter. The Mark IV variant was equally unsuccessful in its daylight bombing role, suffering major losses in the early stages of the war.

The Fairchild Bolingbroke was a Canadian-built variant used as a maritime patrol aircraft by the Royal Canadian Air Force during the Second World War. Built by Fairchild-Canada, it was a variant of the Blenheim Mk IV bomber.

Below is a list of Blenheim and Bolingbroke airframes that survived military service.