While serving as an OSS intelligence officer in Europe in May 1945, Helms wrote a letter to his son Dennis, then three years old, using stationery he had recovered from Adolf Hitler's office in the ruins of the Reich Chancellery in Berlin. He dated the letter "V-E Day" (May 8, 1945), the day Germany surrendered. Sixty-six years later, Dennis Helms delivered the letter to the CIA; it arrived on May 3, 2011, the day after the death of Osama bin Laden. It now resides at the private museum at CIA headquarters in Langley, Virginia.