Volume 3: Safety Behind Bars is the third volume of Image Comics' The Walking Dead that includes issues 13-18.
After being forced to leave the Greene Family Farm, Rick's group stumbles upon what seems to be a permanent sanctuary, an abandoned prison. Soon after clearing one cell block and settling in, the survivors learn that they are not the only residents of this prison and realize for the first time that the greatest threat to their survival in this new world may not be the dead but the living.