"Killer" is a song by Italian singers Baby K and Tiziano Ferro. It was released on 25 January 2013 as the second single from Baby K's first studio album, Una seria.
The lyrics of the song were written by Baby K and Tiziano Ferro themselves. Ferro was also the producer of the album together with Michele Canova Iorfida; the music was composed by Ferro, Baby K and Canova.
The single was released on January 25, 2013, a few days before "La fine", the seventh and last single from Ferro's album L'amore è una cosa semplice.