At the outbreak of World War II in September 1939, "Admiral Scheer" remained at anchor in the Schillig roadstead outside Wilhelmshaven, with the heavy cruiser . On 4 September, two groups of five Bristol Blenheim bombers attacked the ships. The first group surprised the anti-aircraft gunners aboard "Admiral Scheer", who nevertheless managed to shoot down one of the five Blenheims. One bomb struck the ship's deck and failed to explode, and two detonated in the water near the ship. The remaining bombs also failed to explode. The second group of five Blenheims were confronted by the alerted German defenses, which shot down four of the five bombers. "Admiral Scheer" emerged from the attack undamaged. In November 1939, "KzS" Theodor Krancke became the ship's commanding officer.