On March 13, 1793, Luise, her sister Frederica and their grandmother went to the French Theater in Frankfurt. They were presented to the King Frederick William II, who never missed a performance. He wrote home to Berlin a few days later, "I was struck by their beauty and can hardly wait for my sons to meet them." Apparently the King was unaware that the Crown Prince was also in theater that evening and instead of looking at the stage, he kept staring at the box where the girls were seated.
The following day, Frau Olenschlager, the wife of the Buergermeister of Frankfurt gave a luncheon. It was there that Luise met the man who was to become her husband. The King made a visit to the girls grandmother. The following day the Crown Prince proposed to Luise and his brother Louis proposed to her sister Frederica. A weeks later the engaments of the two sisters to the Princes of Prussia were officially announced and celebrated at Darmstadt. "It is she...and no other creature in this world" so described the Crown Prince his reaction to his first sight of Luise in the Frankfurt Theater. Indeed, it was one of the few love matches within the Hohenzollern dynasty.
The war was still in progress, but the King sent word to Fritz and Louis that they would have an extended leave from the army. The double wedding was set for December 1793.