The infamous wolf pack graced the red carpet for the last time as the unexpected <em>Hangover</em> trilogy premiered its last installment of the bro-mance comedy, <em>Hangover III</em> in Los Angeles. Stars Zach Galfianakis, Ed Helms, and newly engaged Justin Bartha drew applause from the hoards of fans, but chanting and howls were reserved for none other than Bradley Cooper.