When Mason arrived In The Return, Tyler refers to him as the 'black sheep'. In this episode Jules wears a sheepskin coat - two wolves in sheep's clothing.
Although he plays the starring role, Paul Wesley, as Stefan, has less screen time than the other starring roles.
Katherine, Jenna, Jeremy and Bonnie do not appear in this episode.
There is a 2005 British horror film, The Descent - Discesa nelle tenebre (2005). In it there are some creatures who look like werewolves, but they are actually called crawlers.