Nick Gehlfuss is just like Us - reeling over Dr. Dean Archer being revealed as the father of Dr. Hannah Asher's baby on Chicago Med. But what will happen when Hannah's ex-boyfriend, Dr. Will Halstead, finds out? "He certainly makes his thoughts known about Hannah and Archer and this news, this bomb of a news," Gehlfuss, 40, exclusively told Us Weekly ahead of the Wednesday, October 8, episode, which will mark the return of his character, Will Halstead.