She has come under attack on the set of her latest movie Five Killers for reportedly being 'extremely unprofessional,' flaking on meetings and making ridiculous demands.

According to celebrity website Bang Showbiz, Heigl has been demanding that she be flown by private plane to and from the film's international locations, and has also requested 'crazy amounts of security.'

Fox News has also reported that an extra on the film 27 Dresses, said that 'Heigl refused to film any scenes until her pregnant assistant ran around and got her a Coke Zero. She refused to eat lunch next to anyone or have anyone speak to her once the cameras stopped rolling.'

'No one on the crew likes her,' an inside source said.

Heigl, 30, made headlines when she publicly bad-mouthed Judd Apatow's Knocked Up, a film that brought her significant box office success.

She further irritated Hollywood when she was nominated for an Emmy on Grey's and then withdrew her name and insulted the writers of the show, saying she didn't feel her character had any "material that was worthy to submit."

'She has a sense of entitlement that is really off-putting,' another source said. 'Many directors that she's worked with in the past do not want to work with her again.'