Bugs - Season 4 Episode 6 Pandora's Box
Overview: The legendary tomb of King Arthur is supposedly at a site, where suddely a lot of people are becoming ill and new owners have stopped all normal work. beckett goes undercover to find out what is going on, and with the help of the others, they discover that the digging for the tomb has unearthed a plague. Alex falls ill with the pague and Ros works at finding her a cure. She is also worried about Beckett, who insists to stay at the site and stop the men from letting more people die and shows for the first time since they split up that she still cares for him.