Shi Jinlong discovered that this case was extraordinary and probably beyond what ordinary police could handle, so he entered the building alone.
Shi Jinlong's special ability, the Yin Yang Ears, essentially allowed him to hear sounds that normal people couldn't, including the voices of restless spirits.
After death, souls transform into restless spirits, which are what people often refer to as ghosts.
However, the vast majority of these spirits return to the Underworld to enter the cycle of reincarnation and start new lives.
Only a very few, due to various reasons, are unable to move on and remain wandering in the realm of the living.
As these spirits are essentially composed of Yin energy, they avoid places with strong Yang energy, thus they are often active in dark and shadowy places, not necessarily only appearing at night.
