While Heidi Klum, Kate Beckinsale and Amanda Seyfried went for full on disguise in their imaginative Halloween costumes, some celebrities didn’t have to look farther than their own wardrobes.

Christina Aguilera arrived at a Halloween party at Pandora nightclub in Hollywood last night dressed as a police officer.

But other than adding a hat and handcuffs, her outfit looked like just another of her usual ensembles.

Under arrest: Christina Aguilera arrives at a Hollywood Halloween party dressed as a police officer

The singer looked to be almost busting out of her tight black lycra dress, which she wore with a leather jacket, fishnet stockings and patent Christian Louboutin pumps.

Aviator sunglasses and bright red lipstick added some glamour but if not for what looked like a children’s police costume cap and the handcuffs, it looked like just another of her typically provocative outfits.

Miss Aguilera, 29, who recently separated from husband Jordan Bratman, looked downcast as she arrived at the Hollywood nightspot with two friends, who looked to have put a lot more effort into their respective costumes.

Lean on me: The singer, who recently separated from her husband, was accompanied by two friends to Pandora nightclub

Her sour mood may be in reaction to onlline rumours this week that she had an affair with Lindsay Lohan’s ex Samantha Ronson.

But the claims have been furiously denied by both camps, with Sam taking to Twitter to say ‘Instead of trying to be clever- I’ll say this in a clear way – NOTHING you’re reading in tabloids about me is true.’

The DJ, sister of music producer Mark Ronson, added frankly ‘It’s all b*******.’

Ronson was spotted leaving Aguilera’s home late at night on October 12 – the day the singer’s separation was announced – after staying for seven hours, but a source close to the singer insists they are simply friends.

Downcast: Christina looked sour as she left the club, after a difficult week which saw her embroiled in lesbian affair claims with Lindsay Lohan’s ex Sam Ronson

Emotional: The 29-year-old said recently of her separation from husband Jordan Bratman, ‘There have been a lot of tears and sadness’

‘They’ve known each other forever and they’re good friends,’ the source told celebrity website Radar Online.

They added: ‘Christina has a ton of gay friends, there’s nothing more to it than that.’

Christina gave an emotional interview to Redbook magazine, explaining her feelings about the breakdown of her marriage to Bratman, with whom she has a two-year-old son Max.

Provocative: Christina is known for her revealing wardrobe

She said: ‘It’s not easy, and there have been a lot of tears and sadness. It’s impossible to redefine yourself and your life overnight.

‘Thankfully, I have my mom and a small group of close friends who are there for me 24/7 and whom I can trust and depend on.

‘On days when it feels impossible to even get out of bed, much less function as a mother, their support and encouragement have kept me moving forward.’