The first image revealed is a grainy black and white photo that shows Sulli sporting what seems to be an eye-patch. Considering that she is acting in the movie 'The Pirates', it seems somewhat fitting. However, like Krystal, Sulli is also expected to have a whole set of images that vary from one another, so stay tuned for the update!
As mentioned before, f(x) will release their 3rd full-length album 'Red Light' on July 7! But, you'll be able to see the girls before then as it has been revealed that they'll be performing on the July 3 broadcast of 'M! Countdown'!
[Update] - SM has slowly started to unveil the other teaser images for Sulli. Make sure you keep checking back throughout the day for more.