Michelle Pfeiffer, who is on the verge of turning 50, dominated the red carpet Monday at the premiere of her new movie "Hairspray" and reminded many that she is still one of the most beautiful women in the business.
To many, Pfeiffer has the quintessential beautiful face. Appearing almost symmetrical, her full lips, high cheek bones and captivating eyes have men swooning and women green with envy.
But what makes someone beautiful and attractive to others is a difficult question to answer. What characteristics, if any, truly define a beautiful face?
There are certain characteristics people possess that make them especially beautiful, like eyes, lips and cheekbones, several professional celebrity and fashion photographers told ABC News. But the importance of symmetry, or when all facial features are lined up perfectly with one another, is something that photographers don't all see eye to eye on.
Nigel Parry, a portrait photographer for more than 20 years, has worked for Vogue and W Magazine, among many others. He has photographed the mugs of Penelope Cruz, Angelina Jolie and Meg Ryan. To Parry, beauty is in the imperfection.
"Superficially, what makes a classic pretty face is generally something a little unusual -- there shouldn't be perfection on both sides," said Parry, who has also shot Mary Louise Parker and Gwyneth Paltrow. "The symmetry should always be off."
Particular features that stand out to Parry as especially pretty are uneven eyebrows and big eyes.
"To me, a classic face is Cate Blanchett, she has a fantastic looking face and the thing with her is she emanates all that's wonderful inside as well," said Parry, who also says that Debbie Harry and Michelle Pfeiffer have "the best mouths."
George Zimbel, who photographed Marilyn Monroe and Jackie Kennedy, said that to him, beautiful faces are the ones that jump out at him, and there is no rhyme or reason as to which ones will catch his eye. Personality, he agrees, adds a lot to a person's beauty.
"[Marilyn Monroe] was so 'on' all the time," said Zimbel, who photographed the icon in 1954 in New York and remembers Monroe's beautiful personality the most. "I don't know how the hell she did it, but she never lost it."
Celebrity photographer Patrick McMullen, who has photographed Kate Moss, Nikki Taylor and Elizabeth Hurley, has a favorite in Pfeiffer, who he has also worked with.
"Michelle Pfeiffer, she's just beyond," said McMullen, who also names Julia Roberts and Elizabeth Hurley as favorites."[Pfeiffer] is just so damn beautiful. She does have the intelligence and she's got the classic beautiful looks. She's so stunning and she's rare."
Katie Ford, CEO of Ford Models, has worked with hundreds of models. She still maintains that it's symmetry that makes a face very beautiful and that the first things she looks at when scouting are eyes, lips and nose.
Ford recognizes uniqueness too, though, and said that today, much of what the fashion industry considers beautiful does have some kind of an edge.
"There is no perfect proportion," said Ford.
One photographer, Mark Robert Halper, who has worked with stars like Tori Spelling and Michelle Williams, believes that symmetry is an important contributor to facial beauty.
"Facial symmetry is a big factor in beauty," said Halper. "We perceive symmetrical faces as prettier."