Actors�Song Joong Ki and Han Hyo Joo were spotted filming for an as-yet-unrevealed project.

A post titled "Shots of Song Joong Ki and Han Hyo Joo filming for an advertisement today" show the two stars hanging out during a break on set, making onlookers wonder what they could be discussing.

Netizens commented, "The two look so good together", "Both of them have flawless skin", "I wonder what it's for?", and more.

You may remember Han Hyo Joo from�the film 'Stakeout' and her�appearance on 'Running Man', while Song Joong Ki is well-known for his hit film 'Wolf Boy' and the drama 'Nice Guy'.