Complex sentence: Keith, Amaretto, and Duncan flee the club, but their car is rammed by vehicles driven by vampires, and after escaping they realize that Duncan has been turned to a vampire, and abandon him in a burning car.
Split into simpler sentences: Keith, Amaretto, and Duncan flee the club, but their car is rammed by vehicles driven by vampires. After escaping, they realize that Duncan has been turned to a vampire, and they abandon him in a burning car.