The return of an iconic entertainment act has animal-rights groups buzzing with opposition. The owners of the Steel Pier in Atlantic City announced their plan to bring back the diving horses, who have not been seen in the resort since 1993. The act is being staged in conjunction with Atlantic City’s new master plan, but faces opposition from groups like the Humane Society of the United States. The diving horse act will be the finale of a 20 minute show at an indoor amphitheater on the renovated Steel Pier.