The way Mila Kunis was giggling with Justin Timberlake at the premiere of their latest movie suggests that her feelings may be more than simply platonic.
But those who know the charismatic pop singer turned-movie star might want to advise caution.
For 30-year-old Justin seems to be one of those men who get cold feet when a relationship starts becoming serious, as was apparently the case with previous girlfriend Jessica Biel.
The former *NSYNC singer reportedly called time on the relationship when the stunning brunette started to talk about marriage.
Prior to that, Justin dated screen siren Cameron Diaz for four years.
Perpetual bachelor George Clooney is another example. The 50-year-old split with his girlfriend of two years, Italian temptress Elisabetta Canalis (below left) shortly after she gave an interview describing herself as a firm believer in marriage.
The silver fox tied the knot once, but it ended after four years and George has since stated that he doesn’t plan on ever giving it another try.
His previous romances with Sarah Larson, a feisty cocktail waitress he met in Las Vegas, and British TV presenter Lisa Snowdon (above right) also failed to go the distance.
Unlike George, Leonardo DiCaprio is partial to blondes – he's dated Glamazons Gisele Bundchen, Bar Rafaeli and Blake Lively – but has so far failed to put a ring on it.
Another bachelor with long-term single status is Hugh Grant, who says he's terrified of ending up "a lonely, sad old man".
The 50-year-old – who has dated glamorous ladies such as Jemima Khan and Elizabeth Hurley – admitted he’s passed up plenty of chances to become a family man.
“I should settle down. It’s all my fault, I’ve had some lovely girlfriends,” he told talkshow host Jonathan Ross.
His fellow British star Simon Cowell has also had plenty of lovely ladies interested in becoming Mrs Cowell.
In fact, the TV mogul – who has a busy career on both sides of the Atlantic – has been engaged to sultry makeup artist Mezhgan Hussainy for 18 months.
Asked earlier this year about the date of the wedding, the 51-year-old joked: "I don't want to overshadow Prince William, so they've got to go first."
For men, like Simon and Sean 'P Diddy' Combs , another jet-setter with a multi-million dollar empire to run, the time never seems to be right to give up their independence.