 Rick and Lori plead for the doors to be opened , while Daryl Dixon ( Norman Reedus ) and Shane attempt to force Jenner to open the doors . He relents because they know if they kill him they will not get the combination to open the doors then all of them would indeed die . Finally , with less than five minutes remaining , Jenner opens the doors after Rick 's pleading with him to let them at least " try " to overcome this tragedy and not be forced to die . Two of the survivors , Jacqui ( Jeryl Prescott Sales ) and Andrea ( Laurie Holden ) , choose to stay behind , but Dale Horvath ( Jeffrey DeMunn ) refuses to leave without Andrea . Before Rick leaves , Jenner whispers something in his ear which leaves Rick visibly shaken . The rest of the group heads for the exits , using a grenade to blow out one of the front windows , and fight their way to their vehicles through several walkers . Andrea and Dale emerge from the building moments before the building detonates ; Jacqui stays inside with Jenner . As Jacqui and Jenner hold hands and let tears drop from their faces , the explosion begins . As the episode ends , the survivors form a vehicular convoy and leave the area , while a massive column of smoke and flame marks the place where the CDC building had stood . 
