DEMI and Ashton, Cameron and Justin, Kate Moss and Potty Pete - they are all at it. I'm talking "boy-toys", of course.

Gone are the days when it was only the done thing for men to date a younger woman. Now, the hippiest thing for a girl to have hanging from her arm isn't just an Hermes handbag - but also an adolescent lover.

Prime explores the trend by pairing 37-year-old divorcee Rafi (Uma Thurman) with David (Bryan Greenburg) who, to her horror, is 14 years her junior.

Yet, he's so hot she can't resist jumping in feet first - even though she is ready to make babies while he is only just out of nappies himself.

But the real sting in the tale comes when Rafi's therapist Lisa (Meryl Streep) realises, after hearing the sordid details of her client's hot, new relationship, that she is in fact David's mother.

And she's not just his mother but also a very traditional Jew with high hopes her son will marry a good, Jewish girl.

Yet, with little chemistry between the two lead roles it is difficult to believe the relationship would have ever taken off Thurman does little to shatter her ice maiden fascade far better suited to her roles in Kill Bill and Pulp Fiction.

However, Streep puts in an excellent comedy performance as a woman torn between her duties as a shrink and a mother. It's just a shame she is working with quite sparse material which fails to reach its true comic potential.

Prime is short and sweet though, presenting us with a semi-interesting, fairly realistic portrait of a very modern relationship.

EB