Written in second person, Deluge tells the story of Dinara, already a mother with two teenage daughters, who finds photos of her parents in the attic of her childhood home. These photos don't line up with what she's been told about her family history, so she goes to ask her stepfather, the only living parent left. This slowly starts to unravel a series of reveals about Dinara's past, all centered around a huge flood that resulted in everything being wiped away.

As Dinara finds out more about her past, she struggles with her anger towards her parents, including her stepfather, for lying to her all this time. It turns out that Dinara is not related to her mother, but was stolen by her right before the flood happened that devastated the entire town, presumably killing Dinara's birth family. Dinara goes so far as to call the police on her stepfather, but finds, in the end, that despite her anger she "cannot un-love her family."