Emil often reminisced over how he first met the plucky and clever Rachel He was ten years old and on his way to America with his parents aboard RMS Titanic - the pride of the White Star Line. On that fateful night, they survived. Barely. A celestial tune echoed in his ears. Years subsequently separated them but a hodgepodge of occasional meetings, accompanied by letters and heartfelt connection, reinvigorated their maturing love. She earned PhDs in rocketry and physics. He became a mechanical engineer and an officer in the Army Air Corps. Fast forward to 1937. Emil must now extract Rachel out of Nazi Germany on the dirigible Hindenburg - the pride of Nazi propaganda. As flames lick the sky, that celestial music rings out again. Many decades later, Emilia Koch, Emil’s great-granddaughter, raptly listens to his diary aboard the Galaxy Explorer as she prepares for her own perilous adventures. And the music appears again. Epoch-making exploits coarse through the Koch bloodline but what truly sustains them is when celestial angels sing.