From Queenpedia.com

Bruce Gowers returned to the Queen fold in October of 1976 to direct a promotional clip for the first single from 'A Day At The Races', the gospel-tinged 'Somebody To Love'. This video was a performance with a difference, in that for the first time it mixed the now standard performance of the song, this time filmed in Wessex recording studios in between recording sessions for the album (they returned to this studio to record the later 'News Of The World' album), with footage from Queen's now legendary free concert at Hyde Park.

The concert, co-organised with future media mogul Richard Branson (whose personal assistant, Dominique Beyrand later became Roger's first wife), and took place on 18th September 1976. The sheer size of the audience, estimated at between 150,000 and 200,000 can be glimpsed in the promo, most notably in the final shot.

Upon it's release on 12th November 1976, the single had already generated massive public support, thanks to Kenny Everett once again, and reached number 2 in the UK charts easilly, again aided by a picture sleeve. However, the first time the song was played on Top Of The Pops, the resident dancers, Pan's People, performed a choreographed sequence to it in place of the promotional video, which was somewhat oddly rarely seen until the 1981 home video release of 'Greatest Flix'.It now features on the 'Greatest Video Hits 1' dvd.