One man was beaten with a metal bar as he slept on a sidewalk in Chinatown, his face mangled beyond recognition in one of the most brutal quadruple murders in the city’s recent memory.

The other stumbled and fell into a manhole in Midtown Manhattan in the middle of the night, an accident that somehow escaped the notice of nearby workers, who later unknowingly sealed him in. He was not discovered until two weeks later.

Days passed in each case without the police or the medical examiner identifying the bodies. In the middle of a teeming metropolis, the two men seemed to be living off the grid and alienated from loved ones.

No frantic co-workers or family members contacted the police to say someone they knew was missing.

Their unsettling deaths revealed the anonymity that shrouds the homeless and others living marginal lives in New York City.