Columbia subject headings:
Detective and mystery fiction.
Missing persons--Investigation--Fiction.
Murder--Investigation--Fiction.
Private investigators--England--London--Fiction.
Harvard subject headings:
Detective and mystery fiction.
Missing persons--Fiction.
Missing persons--Investigation--Fiction.
Murder--Investigation--England--Fiction.
Murder--Investigation--Fiction
Private investigators--England--Fiction
Private investigators--England--London--Fiction
Princeton subject headings:
Fiction.
Missing persons--Fiction.
Novels.
Private investigators--England--Fiction.