I have never done this cruise, but I have looked into it. The murder mystery part is done by Whodunit Production. They do cruises on the FOS and LOS. This looks to be the only 2009 cruise on LOS. When you book be sure to say you want the "MYSTERY ON THE HIGH SEAS" there is an extra charge for this. I will PM you the website. It's a commercial website so I don't want to post it here.
Aug. 29 - Sept. 5, 2009 Royal Caribbean Liberty of the Seas 7 Nights From Miami to Eastern Caribbean.