Kelvin Moore and his wife Elaine return to the apartment building where they grew up for a birthday party at Elaine's sister, Alicia and Kelvin ends up being murdered in the hallway. Kelvin is somewhat of a local hero: he grew up in tough circumstances, got a degree in accounting and has made a good life for himself and his wife, but he never forgot his old neighborhood. Elaine's account of the murder doesn't quite add up and our CSI's figure out she’s been having an affair with an ex-con. He seems like a good suspect, but as Mac and the team dig deeper, they figure out that some neighborhood drug dealers hid drugs in Alicia's house and she ended up destroying them. In a series of mishaps, Elaine tries to help her sister, but the plan fails and the drug dealers kidnap Alicia's daughter. Our CSI's manage to unravel the case and rescue the little girl. Also Christine brings loads of presents to Lucy's first birthday, endearing her to Mac's team.