Lilja´s newest book, Netið ((Tangle) was published by Forlagid publishing in October 2016 and is the second book in the Reykjavík Noir Trilogy.
Lilja started her writing career in 2008 when she sent a manuscript of a novel to a competition run by the publishing house Bjartur whose aim was to find the Icelandic Dan Brown. Lilja got a publishing deal out of the competition and in 2009 her first book, the crime novel Spor (Steps), came out, which she wrote in her spare time. Her second book, Fyrirgefning (Foregiveness) was published a year later but after that Lilja wrote mostly for theatre for the coming years. She won the Icelandic Theatre Awards for Best Play of the Year in 2014 for her staged debut Stóru börnin (Big Babies). But in 2015 she started a new crime series with Icelands biggest publisher Forlagid. The series has been called The Reykjavík Noir Trilogy, and the first book in series, Gildran (Snare) became an instant success.