Cameron Diaz and Justin Timberlake back together, on set of new movie

The former couple were all smiles, as they filmed scenes for Bad Teacher

They might have split back in 2007, but there's clearly no hard feelings between Cameron Diaz and Justin Timberlake - the pair were all smiles this week on the set of their new movie, Bad Teacher.

Clearly enjoying the reunion, the former couple were spotted joking around as they filmed scenes on location. And apparently, their spark is more than apparent when they share the screen.

A source revealed to Star magazine: 'Their chemistry is incredible. Cameron was craving a high-energy comedy and sexual sparks, and she's definitely getting that with Justin! She positively glows when she's around him.'

Bad Teacher sees Diaz playing a school teacher who gets dumped by her boyfriend. Timberlake takes on the role of a substitute teacher, who Diaz sets out to seduce.

Cameron and Justin dated for four years, before they split back in 2007. The break-up was reportedly amicable - and if these pics are to be believed, the pair have remained firm friends.

Now we wonder if Jessica Biel is so happy to see her beau and his ex reunite?

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