"¿Quién será?" (English: "Who Will It Be?") is a bolero-mambo song written by Mexican composers Luis Demetrio and Pablo Beltrán Ruiz. Beltrán recorded the song for the first time with his orchestra in 1953. Pedro Infante, for whom the song was written, recorded it in 1954.
The first rendition of Luis Demetrio's "¿Quién será?" was recorded by Pablo Beltrán Ruiz with his orchestra as an instrumental cha-cha-chá in 1953. This version was later included on the LP South of the Border / Al sur de la frontera – Cha-cha-cha. According to Demetrio, Beltrán only contributed the first few chords of the song. The rest of the composition and the original lyrics (in Spanish) were all written by Demetrio. However, because Demetrio sold his rights to Beltrán, the song has often been misattributed to the latter.
Beltrán re-recorded the song on numerous occasions including an upbeat cumbia version for the album Mister Cumbia (1966), a ska version for the album Caliente, caliente... a go-go (1966) and a boogaloo version for the album Rosita bonita (1968), all released by RCA Victor.
