Headliner
From Vanishing Point Wiki
SPOILER
The small pictures of Houdini along the bottom are actually signals representing letters. The code/language of Semaphore is used, among other things, for nautical signaling. A quick Googling for images of Semaphore will yield a primer. Thus, the message along the bottom reads:
OPPOSITE
The skywriting clue from Australia was DARK [1].
Thus, the answer is: LIGHT
To next puzzle: Seven Card Monte.
![[1]](http://vanishingpointwiki.com/wiki/Image:SkyType_Sydney2.jpg){kind=link}