There's a mysterious epidemic about on tonight's Eleventh Hour, and Jacob Hood must get to the bottom of it once again.  The special agent for scientific cases must discover the reason for the sudden deaths, and he travels to Georgia to do so. 

On “Cardiac,” 11-year old boys are struck suddenly with heart attacks despite being relatively healthy.  Dr. Jacob Hood (Rufus Sewell) has to find a way to prevent the casualties from occurring, as well as determine what's causing everything.  Tagging along is his female bodyguard, Rachel Young (Marley Shelton).  

They are joined by the local law enforcement, working on the case intently.  Together they search the place for signs that would lead them to the probable origin of the crime.  Battling numerous hindrances to the truth, Hood and Young try their best to prevail and find the root of the mystery. 

Written by Mick Davis and directed by Clark Johnson, “Cardiac” features a number of guest stars.  It's likely that a lot of them will be playing the victims of the heart attacks.  Joining Sewell and Shelton as cast on the episode are Nicole Butler, Regina Hoyles, Chip Hormess, Brown Zach Mills, Steven Walsh Jr., Daniel Roebuck and Erica Gimpel. 

Below is a preview of “Cardiac,” where you can see Dr. Jacob Hood deducing the fact that the weak are being targeted.