Liv Tyler and Kate BosworthWhose steamy lip lock?Every now and again we come across something which shocks and confuses us.

And trust us, that's hard.

So, what is it, we hear you cry?

Well, while Liv Tyler enjoyed a spot of lunch with Smother co-star Dax Shepherd, on the table next to them happened to be Kate Bosworth and Helena Christensen.

So far, so innocent.

But don't be fooled.

As Liv and Kate got up to exchange hellos, they greeted each other with what can only be described as an over-friendly embrace.

Rather than a celeb air kiss, the lovely ladies locked lips.

So, we're left to wonder if this was a publicity stunt, a dare, or something a little more meaningful.

Have a look in the gallery and see what you think.