Lindsay Lohan was caught in the middle last night when her ex-lover Calum Best showed up to see her girlfriend Samantha Ronson DJ.

The lady lovers – who are currently visiting London to show off Sam's DJ-ing talents and Lindsay's partying skills – reportedly had their night ruined by the Mean Girls' former flame.

Hundreds of guests turned out for the evening entitled 'F*ck Rehab' at Chinawhite in London to see Hollywood's favourite lesbian couple grinding in the DJ booth.

A insider tells the Daily Mail, “Lindsay was horrified when she found out Calum was there and refused to talk to him.

“Samantha gets jealous of her former male lovers, and Lindsay didn't want to upset her.”

The girls reportedly put on quite a show for fellow revellers, with some very public displays of affection in the DJ booth.

See them both in action below: