One of the most powerful and expressive scores of TV series shows in modern times, the man and musician that composed all the beautiful and meaningful music on Penny Dreadful is Abel Korzeniowsky; Abel is one of the most brilliant Polish musicians, he was born in Krakow and graduated from the Academy of Music of the same city.
Abel composed only scores for Polish movies and theater plays initially, but after some time he became known also in the rest of the world, winning the San Diego Film Critics Society Award in 2009 ad being nominated for the Golden Globe.
The tells that he had always loved music, since his mum played the cello in opera. He also plays the cello; in a very interesting interview he tells also about his anxiety problem; he was not happy playing in front of an audience, too much stress. So, he thought that composing for movies was more his thing, and he was totally right I would say.
He always had the dream of coming to Hollywood, so he contacted several agents in Los Angeles, and finally, he succeeded.
Here is the link to his music, from the first season of Penny Dreadful. You can also listen to his scores from the second and third season.