The Key in Steam is shown as "Product already owned".
Other Keys that have been shown as "Product already owned" were completely valid and working!

About This Game

Hydrophobia: Prophecy is the ultimate version of this jaw-dropping action-adventure set onboard a floating city, where terrorists take control and heroine Kate has to overcome her haunting childhood memories to fight back using all her skills and expertise as a systems engineer.

Good luck, Have fun and Game On

Steam Group for early announcements of Giveaways
See http://steamcommunity.com/groups/freshaways

P.S. If you have any problems with a key or anything else, contact me on steam. Thanks.