he opened his mouth to swallow some of the liquid before he threw the limp body roughly aside , watched as it slumped heavily onto the ground ; and then , as the present swung back and their surroundings exploded with flashes of light , the murderer walked on down the road , searching for his next victim , blackening and shrinking into a vague half-life , evaporating into the air as the present shifted back for the last time and settled around them .