As it happens every year, the 56th annual Grammy Awards featured a number of surprise, and at times somewhat far-fetched, collaborative performances. Among them was an unlikely pairing between R&B heartthrob Robin Thicke and classic-rock icons Chicago.

After an enthusiastic introduction by Grammy host LL Cool J, who highlighted Chicago's legendary horn section, the band launched into 'Does Anybody Really Know What Time It Is?,' the Top 10 single from 1970's timeless debut 'Chicago Transit Authority.'

The group and Thicke continued trading lines as they segued seamlessly into 'Beginnings' and the No. 3 smash 'Saturday in the Park' (the band's highest-charting single ever), before ending with Thicke's 2013 radio hog 'Blurred Lines.'

Thicke is the progeny of actors Alan Thicke and actress Gloria Loring. After achieving isolated bursts of success over the past decade, Thicke enjoyed a breakthrough year in 2013 with his hit ‘Blurred Lines’ and its very racy music video.

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