When we saw Katy Perry on the arm of a well-dressed, clean-shaven young man last week in New York, we assumed she’d traded her on-again-off-again boyfriend John Mayer for a better-looking model.

But it turns out this mystery man was in fact John; just with short hair, a fresh face and clean clothes.

So why the sudden change in appearance? Well apparently it’s all down to Katy.

The Wide Awake star got 35-year-old John to clean up his act because he looked too much like her ex-husband Russell Brand.

 

“Katy’s had it with the grungy, bohemian rock-star look. She’s over it,” a friend of Katy, 27, told heat exclusively.

“She’s basically given John an anti-Russell makeover. She likes him to wear smarter clothes – ones that don’t smell – and cut his hair."

Clothes that don’t smell? That seems fair to us…

“She’s looking for a cleaned-up version of her ex.”

 

Are things getting serious?

And surprisingly bad boy John’s been more than happy to oblige. Maybe it’s because things are heating up between them?

“Things are getting more serious,” says another friend close to the couple.

“Katy is even dreaming of them living together in New York – John already has a place there. She has sold the place she owned with Russell and is looking to buy somewhere else.”

Katy started dating musician John in August, but the couple had a short break last month amid reports that Katy was fed up with John’s wandering eye.

Since getting back together, things have been going great for them and even Katy’s sceptical friends and family are being won over by the notorious womaniser, who's dated Jennifer Aniston, Taylor Swift and Jessica Simpson.

“Her friends and family are starting to realise that John is more like Katy than Russell ever was,” says the insider.

“They have a great connection and are always laughing.”

So what do you think – do you prefer the old John, who wore smelly clothes, or the new John, who actually looks pretty damn hot?

Tough decision, eh?

Read the full story in this week’s heat magazine – out now!