Wandering alone in New York she is recognised for what she is by a wise old rabbi who takes her in and helps her learn how to behave like a human so she can live among the Jewish community.
At the same time in the Little Syria neighbourhood of Lower Manhattan, a tinsmith called Arbeely is repairing the dents in an old copper flask. As he touches it with his soldering iron he releases the Djinni trapped inside by a wizard centuries earlier.
For a while the Golem and the Djinni lead separate lives, struggling to make their way in this strange new place. She takes the name Chava and goes to work at a bakery; he calls himself Ahmad and learns to be a tinsmith.
Everyday life is tedious beyond belief for both of them. Needing neither to sleep nor eat, to fill the long hours without giving themselves away is a grim challenge.
The Djinni, although pining for his glass palace in the desert, at least can spend his nights exploring New York but the Golem, being a woman, is trapped indoors after dark and occupies her time unpicking and sewing up the same garment over and over again.
At long last they meet and, recognising each other's true nature, the pair become uneasy companions, then soulmates until finally discovering the shattering way their fates are linked.
This is an epic novel - possibly too epic. I get that Wecker has to convey how dull and repetitive human life is for her folklore creatures, but she might have done so in fewer words. To me the book feels about 50 pages overlong.
Despite that, it is an enjoyable read: original, unusual, sensitively written. Wecker succeeds in bringing together Jewish and Arab myth and immigrant history, as well as bringing to life New York at the turn of the 20th century.
But her greatest triumph is the way she weaves in real human characters - Saleh the tragic icecream seller, kindly coffee-house owner Maryam Faddoul and spirited socialite Sophia Winston.
She somehow makes it seem as if magic might really be out there hovering at the edges of our lives just a little out of sight.
The Golem And The Djinni is out now.