Because it's Reese's birthday and because there are no new numbers, Finch gives Reese the day off. However, there is a new number that Finch believes would not be a good case for Reese to work on, since it may hit a little too close to home regarding the nature of the death of his ex-girlfriend, Jessica Arndt. Reese is aware of Finch's motives. That number belongs to Karen Garner, who Finch is pretty sure is the victim. He is certain that Karen Garner is an assumed name and that she is on the run from someone, probably a violent boyfriend or husband. The case does hit home for Reese who decides to take matters into his own hands much like he would have handled the situation if the woman was Jessica. This situation doesn't sit well with Carter, who has been asked by FBI Agent Donnelly to assist in the investigation on Reese and finding his DNA at a past crime scene in New Rochelle, that crime scene being the death of Jessica's husband, Peter Arndt. Finch encourages Carter to join that investigation knowing what she will find out about Reese. She ends up finding more than Finch anticipates. And Finch's mysterious birthday present of a key to Reese becomes a little less mysterious when Reese learns to where that key unlocks.