Searching for the true killer of Count Drebber, Sherlock and John set a trap for the culprit using a wedding ring found at the murder scene as bait. After a struggle in which the ring is lost, Sherlock is able to deduce who the real killer is.
I came at this from two
different lines of reasoning.
.استنتجت هذا بمنطقين
Ich kam durch zwei Gesichtspunkte
zu diesem Ergebnis.
Concluí esto a partir de dos líneas
de pensamiento distintas.
J’ai suivi deux pistes pour cette affaire.
Cheguei a essa conclusão por meio de
duas linhas de raciocínios diferentes.
Я анализировал это дело
 по двум направлениям.