For a few minutes, and only a few minutes, passers by might be startled by a voice, singing, as if from nowhere. The more perceptive might think its source is from below their feet, perhaps escaping through a metal grate, but they cannot quite pin it down.
The voice is female, and is obviously trained to a high degree. The words are in Latin. The poignancy is breathtaking.
Lacrimosa dies illa
Qua resurget ex favilla
Judicandus homo reus.
Huic ergo parce, Deus:
Pie Jesu Domine,
Dona eis requiem.
Amen.