The Trans-Siberian Orchestra (often abbreviated to TSO) is a progressive rock band founded in 1993 by producer, composer, and lyricist Paul O'Neill, who brought together Jon Oliva and Al Pitrelli (both members of Savatage) and keyboardist and co-producer Robert Kinkel to form the core of the creative team. The band's musical style incorporates classical, orchestral, symphonic, and progressive elements into hard rock and heavy metal. The orchestra is most famous for their Christmas-themed series of rock operas (Christmas Eve and Other Stories, The Christmas Attic, and The Lost Christmas Eve), for which they do an annual winter tour. They have also released two rock operas that are based on historical themes (Beethoven's Last Night and Night Castle). They are also known for their extensive charity work and elaborate concerts, which are complete with a full orchestra, a massive light show, lasers, dozens of pyrotechnics, moving trusses, video screens, and other effects that are synchronized to the actual music.