Whether they like it or not.
The weather in the city of High Scape is off the charts. It's snowing in the middle of summer, and the townsfolk are desperate for Shield Lee Mallorough and Source Shintaro Karish to fix it-which they can't do. But try explaining that to an angry mob...
Meanwhile, there's a crazed killer targeting aristocrats. Karish has forfeited the Dukedom of Westsea to continue working as a Source, but Lee fears that technicality won't matter to the murderer. It certainly doesn't matter to Karish's mother, who's bound and determined that he take the title.
Only by working together will Lee and Karish be able to figure out the weather, catch the killer before it's too late, and most importantly...get rid of Karish's mother.