After the Royal Navy's bloody high seas campaign to kill the mighty Bismarck, the Allies were left with an uncomfortable truth?the German behemoth had a twin sister. Slightly larger than her sibling, the Tirpitz was equally capable of destroying any other battleship afloat, as well as wreak havoc on Allied troop and supply convoys. For the next three and a half years the Allies launched a variety of attacks to remove Germany's last serious surface threat. The Germans, however, had learned not to pit their super battleships against the strength of the entire Home Fleet outside the range of protecting aircraft. Thus they kept Tirpitz hidden within fjords along the Norwegian coast, forcing the British to assume the offensive. This strategy paid dividends in July 1942 when the Tirpitz stirred from its berth, compelling the Royal Navy to abandon a Murmansk-bound convoy in order to confront the leviathan. The convoy was ripped apart by the Germans, while the Tirpitz returned to its fjord. Trying an indirect approach, the British launched one of the war's most daring commando raids?at St. Nazaire?in order to knock out the last drydock in Europe capable of servicing the Tirpitz. Of over 600 commandos and sailors in the raid, more than half were lost during an all-night battle that succeeded, at least, in knocking out the drydock. It was not until November 1944 that the Tirpitz finally succumbed to British aircraft armed with 10,000-lb Tallboy bombs, the ship capsizing at last with the loss of 1,000 sailors. About the Authors Military historians Niklas Zetterling and Michael Tamelander, authors of Bismarck, (Casemate 2009), are widely-acclaimed for their detailed new research on key World War II subjects. ILLUSTRATIONS: Throughout