"Step Inside Love" is a song written by Paul McCartney (credited as "Lennon–McCartney") for Cilla Black in 1967 as a theme for her TV series Cilla, which first aired on 30 January 1968.

In late 1967 McCartney was approached to write the theme by Cilla and her series producer Michael Hurll. He recorded the original demo version at his London home, accompanying himself on guitar, which consisted of just one verse and the chorus.

Black's recording of this song was used as the theme during the early weeks of the show, until it was decided that the song needed an additional verse, so McCartney came to the BBC Theatre and wrote it there. According to Hurll, the opening line of the second verse ("You look tired, love") came from McCartney's observation of Cilla looking tired from the long rehearsals for the TV show. McCartney then added a third verse and this version was recorded as a studio demo at Chappell Studios in London on 21 November 1967, with McCartney on guitar accompanying Cilla on vocals. This demo was the basis for the single, although where the McCartney demos were recorded in the key of D, the final arrangement of the single version was transposed up a fourth to G, to take advantage of Cilla's higher register.

The single version of the song (with Cilla singing live over the studio backing track) was premiered on 5 March 1968 edition of her show; the single was released on 8 March 1968, and reached number eight on the British charts in April 1968. The record also reached Number 15 in Ireland in the same month. The recording was also featured on Black's third solo studio album Sher-oo! Remixed club versions of Cilla's original 1960s vocal were released in 2009 on her album Cilla All Mixed Up.

In 2002, DJ Tommy Sandhu managed to coax Cilla back into the recording studio to re-record "Step Inside Love". Sandhu then remixed the song and 3,000 white labels of it were sent to British clubs under the name "TS vs CB". The 12" charted at number three on Music Week's club chart. A maxi single of all of these remixes was released to download worldwide on 30 November 2009.

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