Knock Knock

"Knock Knock" is a song by American R&B recording artist Monica. It was written and produced by rappers Missy Elliott and Kanye West for her fourth studio album After the Storm (2003). Commissioned following the delay and subsequent reconstruction of Monica's third album All Eyez on Me (2002), the song is built around excerpts of the composition "It's a Terrible Thing to Waste Your Love" (1976) by American vocal group The Masqueraders. Due to the sample, Lee Hatim is also credited as a songwriter. On breezy, summer-tinged "Knock Knock," a blending of 1970s-style soul and hip hop set against steely keyboards and a stony bass, the protagonist warns a cheating boyfriend not to come calling.