"Chain Reaction" is a melodic R&B song, sung by Diana Ross, and written by the Bee Gees, who also provided the backing vocals for the single. The track was released on Ross's 1985 album Eaten Alive, and as a single twice - in 1985 and again in 1986.

According to the Gibbs biography, the brothers had initial reservations about offering the song to Ross in case it was too Motown-like for her.

The single became Diana's second No. 1 hit in the UK Singles Chart. The song also hit No. 1 in Australia and was the top selling single of the year (1986) in that country, also reaching the top of the charts in Ireland and Zimbabwe. In New Zealand, it peaked at No. 3 and also made the top 5 in South Africa. In 1993, the song broke the UK top 20 again (also breaking the top 40 in Ireland and France) when it was re-released to commemorate her 30th anniversary in show business.

The song fared poorly in the US, where it initially peaked at a disappointing No. 95 on the Billboard Hot 100 late in 1985. A few months later, a remixed version of the song was issued as a single (Ross performed this version of the song on the American Music Awards, which she hosted that year). The new version re-entered the chart and performed better, but with the diminished momentum, it stalled at No. 66 on the Billboard Hot 100 and No. 77 on Cash Box. More than thirty years later, the song remains Diana Ross's final appearance on both charts.

At the beginning of the video is in black-and-white, Ross enters the TV studio and proceeds to perform the song in front of dancing spectators in a '60s-style live TV. The performance is intercut with a view from the station control room where producers are shown additional scenes appearring in colour, confounding them on where the scenes are coming from. Half-way through we see Ross walking up a desolate street with barrels of fire littered around and dancers in the background. Careful lighting and fog help create the effect Ross is performing on a real street. It is the only time the street is shown and the video eventually returns to the TV studio performance. The final style of scene has Ross performing in what is supposed to be the glamorous front exterior of the TV studio. A quick shot of the control room is shown with the lead producing yelling in shock or frustration, before the scene continues. It's assumed the producers have lost control of the broadcast. The video ends with intercuts of the TV performance, the exterior, and the control room. The band finishes in the black and white scenes of their show, dancing with the audience and using a combination of both color scenes. A producer gets in a cab from a nervous breakdown.

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