Frédéric Chopin wrote his Nocturne in C sharp minor in 1830, though it was never published during his life. He dedicated this work to his older sister as an exercise to prepare for the study of his second concerto. It was first published in 1875, as an Op. Posth. without number. It has come to be known by its Brown catalogue number, B. 49. The piece was famously played by Holocaust survivor Natalia Karp for a nazi concentration camp commandant, leaving him so impressed with the rendition that he spared her life. Marked lento con gran espressione, it features a soft introduction and a dramatic melody played over a quaver bassline. The piece was featured in many films, the most popular being The Pianist. Two versions exist of the score, with the Henle Urtext being the most commonly accepted, though it differs from the manuscript in very specific points.