Two things are clear to Desiree Rosenqvist from the Stockholm police: This letter was written in complete despair and paranoia. And it contains secret details of an old murder case. Desiree contacts Sam Berger, who sets off with Molly Blom to northern Sweden: What lies behind this letter? But someone wants to stop them at all costs from uncovering the truth. However, that's not their only problem - after the revelations of their last case, they are being pursued by the intelligence service. And they don't even know if they can trust each other.