YOU have the perfect husband, the perfect child and the perfect house. Now another woman wants what you ve got…and she s obsessed. Beyonce Knowles and former Canning Town schoolboy Idris Elba star in psychological thriller OBSESSED (12A), the new Fatal At

YOU have the perfect husband, the perfect child and the perfect house.

Now another woman wants what you've got...and she's obsessed.

Beyonce Knowles and former Canning Town schoolboy Idris Elba star in psychological thriller OBSESSED (12A), the new Fatal Attraction.

Sharon Charles seems to have a charmed life, until husband Derek meets a new temp at the office.

Lisa (Ali Larter) is beautiful, poised, and perpetually cheerful so when he finds her crying at work over a boyfriend, he tries to comfort her.

Then Lisa comes on to him at the company Christmas party, and he firmly tells her she's got the wrong idea. The next day she tries again. Lisa won't take no for an answer, and begins to become more and more unhinged with each and every refusal. Soon, Derek becomes terrified by how far it appears Lisa's obsession will go.

At first Derek says nothing about Lisa to his wife, thinking he has things under control. He resolves to fire her but finds she's already quit, and he believes Lisa is gone from his life.

But a few weeks later, Derek receives a series of eerie, sexual e-mails, all from the same sender: "TEMPGIRL."

Sharon is pulled into the triangle as Lisa tries to drive a wedge between him and his wife.

When Sharon comes home one day to find that Lisa has been inside her home, she's had enough...and takes matters into her own hands.

What started as an office flirtation culminates in a shocking, no-holds-barred, violent and bloody standoff between two women who both feel they have everything to lose - and they're willing to die to keep from losing it.

Elba, who briefly worked the night shift at Ford, Dagenham, but is now based in the US and is best known to viewers of hit TV series The Wire, says: "Three films into my relationship with (movie company) Screen Gems, and they say, 'Want to do Obsessed? You're going to be working with Ali Larter and Beyonc�.' I was like, 'Wow, that's tough.'"

He adds: "Working with Beyonc� is definitely an experience. The image of Beyonc� is huge. She's an amazing talent.

"But when she gets on the set, she's very much an actress. She's very dedicated to the film, to the role.

"I remember the first day we met. We had to do this photo shoot for some of the pictures in the house.

"It literally went, 'Idris, this is Beyonc�. Beyonc�, this is Idris. Now you've met each other, we need to see you stand over there and kiss.'