As the title suggests, a kidnapping is at the center of this case of the week. A baby is kidnapped and the parents claim to have heard strange voices through the baby monitor.

The CSI team comes from Quantico to Baltimore to investigate that case.

The team begins to believe that the kidnappers knew what they were doing after realizing that the baby monitor was stolen.  

Through the husband's computer the team figures out that someone has been monitoring all emails and searches involving "baby" and "Caleb." 

Avery believes that the Caleb's mother is having an affair based on her phone records. The team is led to a suspect and discovers that Fran was having an affair with him and that Caleb is really his child, except that the baby the team discovers is not Caleb. 

The team follows a lead on a couple who sold the baby, but when they arrest them the two criminals are shot and the team must pursue the shooter. 

Avery and Mundo realize that they have discovered a baby auctioning ring and that three more babies have gone missing. 

Grummitz realizes that the baby camera company has a problem with their source code, which is allowing the hacking to occur. 

The team tracks down the location of the cyber criminals. The team chases down two other baby smugglers and has a close call with Caleb.