4. Balthazar used a spell to send Sam and Dean into another reality. He compared the danger they were facing to a scene of which well-known movie?
From Quiz "Supernatural" "The French Mistake"
Answer:
The Godfather
Balthazar appeared, and began gathering ingredients for a spell. He told the brothers, "You've seen 'The Godfather' right? You know at the end where Michael Corleone sends his men to kill his enemies in one big bloody swoop!" He continued, "Moe Green gets it in the eye, then Don Cuneo gets it in the revolving door . . ." Sam asked why he was talking about the movie, and he replied, "Because we're in it, right now, tonight. And in the role of Michael Corleone, the Archangel Raphael." He then told them Raphael had "put out a hit list on every last Samaritan who helped our dear Cas, including both of you - and SO much more importantly, me." When Virgil showed up, he gave them a key and flung them through a window, where they landed on set.