Can someone help me with the Hush Mission in Batman Arkham City?

I've complete the main tory for Arkham city. I've completed the first unidentified murderer case but have not done the second. I've spent hours going round the map and have not received the notification about the second mission. what is going on?Can someone help me with the Hush Mission in Batman Arkham City?
Yeah overall the HUSH side mission is annoying you have to pinpoint dead bodies and if you dont know where to look it is seemingly impossible. I actually ran in to a few bugs during this side mission which made it even more frustrating. A good place to go and actually has a map is IGN.com is a fantastic site. Which helped me out, though i did have to still do some searching. But you have to physically search for the bodies and scan them.Can someone help me with the Hush Mission in Batman Arkham City?
You NEVER get a notification, you have to find it yourself. OR, use a video guide, which is always useful. That's what I did, bro.

http://www.youtube.com/watch?v=BmZBeXY_GWk Have fun!Can someone help me with the Hush Mission in Batman Arkham City?
IGN.com has a guide for that. Just look it up on their site.