Behind the gates of the world's most impressive castles, manor houses and mansions are secrets waiting to be revealed. See these amazing structures in all their glory and hear the remarkable, mysterious and bizarre tales tied to the rich and powerful who once resided there. From a German castle where a real life Dr. Frankenstein tried to breathe life into the dead to the magnificent Highclere Castle, which is now the setting for Downton Abbey, but was once the home of an English lord who unearthed King Tut's tomb, these stories will captivate and amaze.

Go inside the castles, manors and mansions with our behind-the-scenes photos, and watch exclusive video of the stories and secrets hidden in their history.