Jessica Niemi is put on leave after a violent altercation between her and a belligerent man makes headlines. To escape the unwanted scrutiny, Jessica travels to a remote island in the Åland archipelago and rents a room at a small seaside inn. She is hoping to be left alone as she faces the possibility that she is losing what is left of her sanity but three elderly visitors have arrived at the inn for their yearly sojourn. Jessica learns that they are the remaining 'birds of spring', former refugees who fled Finland as children during World War II and lived together for a few months in an orphanage on the island.

The orphanage no longer exists but the local legend about one of its inhabitants, a girl named Maija, still haunts the surviving orphans. Every evening Maija would put on her blue coat and stand on the pier, looking out at the dark water until one night, she disappeared and was never seen again. When one of the 'birds of spring' is found dead, drowned alongside the same pier, and Jessica learns about two other deaths from the past, also connected to the orphanage, she has no choice but to try and put the pieces of this terrifying mystery together.

Jessica can't be sure whether she's facing a killer or--just like the legend says--the ghost of Maija, the girl in the blue coat. Uncertain what is real and what is not, Jessica desperately searches for answers that she hopes will stop the murders and finally silence her own demons once and for all...