Lightbox gallery implementation from one image

So here is the deal, I want to enable the user to click on the post image and then a light box effect is activated. The light box would then show a gallery of images linked to the post.

The link below allows the user to navigate the images ( a nextGen gallery) using the arrow buttons.

http://www.tejusanusi.co.uk/2011/htc-wildfire-facebook-competition/

Hope this makes sense.

Thanks

Tej