Diamonds dazzle on the red carpet

As always, dazzlingly lavish diamonds were everywhere, and jewelled necklines were a particular theme.

Dame Helen crowned for Queen performance

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Strapless and single-shouldered gowns were ubiquitous, smattered with trimmings of feathers, antique lace and bows.

One star who opted for sleeves, however, was The Queen star Dame Helen Mirren, whose regal champagne scoop-necked frock by Christian Lacroix was widely admired.

With a delicate lacy finish, it was slightly ruched around the waist to give the 61-year-old star a stunning outline.

Rachel Weisz impressed in a strapless almost-metallic oyster gown in satin by Vera Wang that moved like mercury, complete with a sweeping train.

A delicate diamond trim on the neckline included a pretty bow.

Weisz paired her dress with a vintage Cartier necklace, but critics said it clashed with the detail on her outfit.

Jennifer Lopez also opted to integrate eye-catching jewels into her dress, in a pale rose Grecian-look Marchesa frock topped with four rows of elegantly draped glittering rocks.

And Beyonce Knowles' barely green, figure-hugging number featured a single strap encrusted with chunky diamonds that crossed her body like a sash.

Dame Helen called her gown, complete with gold-leaf embroidery on the skirt, her "dream dress".

"It shows me," she said.

"It makes me feel comfortable. I don't feel like I'm trying to be something I'm not."

While black was not a popular choice, there were plenty of other dark hues on display.

The British star of The Devil Wears Prada, Emily Blunt, wore a sequinned blue gown by Francisco Costa by Calvin Klein.

Maggie Gyllenhaal's Proenza Schouler frock mixed black and navy and threw in a one thick shoulder strap, Venetian glass embroidery and a feathered hemline.

Presenter Ellen DeGeneres's partner Portia de Rossi also went for a dark blue, in a halter-neck number by Zac Posen.

Reese Witherspoon picked an intense deep purple bustier dress by Nina Ricci with voluminous tiered ruffles descending to the floor, finishing the look with Van Cleef & Arpels jewels.

Cate Blanchett's one-shoulder steel-coloured Swarovski crystal mesh gown by Giorgio Armani Prive was another favourite with the fashion lovers assessing the looks at the Kodak Theatre in Los Angeles.

Leading the pack for those preferring a lighter touch was Volver star Penelope Cruz, in a breathtaking strapless blush Versace creation.

Its tight bodice wove the fabric into intricate waves and swirls before giving way to an enormous, feathered full skirt.

Kate Winslet's simple but effective mint green gown by Valentino again had a Grecian theme, with unfussy ruching across the chest that lead to a single strap trailing over her shoulder right down to the ground.

Bolder choices came from Gwyneth Paltrow, Jessica Biel and Nicole Kidman.

Paltrow's burnt apricot Zac Posen frock in tulle and chiffon used clever art deco patterns, while Biel opted for a hot pink halterneck from Oscar de la Renta.

Kidman picked a bright red Balenciaga halter gown with an oversized bow tied at the neck.
Her close friend had no qualms about clashing in a yellow Escada gown was yellow with a sapphire blue sash.

Cameron Diaz was one of the few celebrities in bright white, showing off a structured Valentino creation.

Jennifer Hudson paired a brown ruched gown with an unusual - and not very well-received - metallic python bolero jacket by Oscar de la Renta.

But 10-year-old Abigail Breslin, from Little Miss Sunshine, charmed in a full pink sundress adorned with flowers.