The Banshee's Keen

 is a repeatable quest in Fallout Shelter.

Synopsis
''We've received reports from nearby Settlers that their building is haunted by a wailing female spirit. That sounds unlikely, but we should investigate in the name of... Science! Don't worry, we'll honor your memory if the angry dead end up eating your souls.''

Objectives
Solve the mystery of a haunted building.

Dialogue

 * Abandon all hope, ye who enter here... (_RaiderLine_1);
 * How deep does this actually go? (_RaiderLine_2);
 * I'm staring into the abyss, but nothing's staring back. (_RaiderLine_3);
 * Why build such a place? It makes no sense. (_RaiderLine_4);
 * What, you can't hear it? But, it's so *loud*! (_Conversation_1_NPCEnd_1);
 * Thank you so much! Here, this might help. (_Conversation_1_NPCEnd_2);
 * Really? It's so loud I can barely make out what you're saying! (_Conversation_1_NPCEnd_3);
 * Welcome Dwellers! Boy are we glad to see you guys. (_Conversation_1_NPCStart_1);
 * That incessant wailing is driving everyone here mad. (_Conversation_1_NPCStart_2);
 * Some say that it's an omen of death, and they might be right... (_Conversation_1_NPCStart_3);
 * People are starting to attack each other! (_Conversation_1_NPCStart_4);
 * What does the wailing sound like? (_Conversation_1_Team_1);
 * Don't worry, we'll take care of it. (_Conversation_1_Team_2);
 * We don't hear anything... (_Conversation_1_Team_3);
 * Then you're one of *them* and you must be killed! (_Conversation_2_NPCEnd_1);
 * You'd better, or we'll kill you too! (_Conversation_2_NPCEnd_2);
 * Okay. Sure. Whatever. Here you go! (_Conversation_2_NPCEnd_3);
 * Nuts? NUTS?! I'll show you nuts! (_Conversation_2_NPCEnd_4);
 * You! Make that noise stop right now! (_Conversation_2_NPCStart_1);
 * We can't think straight anymore... (_Conversation_2_NPCStart_2);
 * Killing other Settlers helps, but just for a little while. (_Conversation_2_NPCStart_3);
 * Sorry, but we can't hear anything. (_Conversation_2_Team_1);
 * Let us through! We'll take care of it. (_Conversation_2_Team_2);
 * Give us your weapons first, then we'll make it stop. (_Conversation_2_Team_3);
 * You guys are nuts! (_Conversation_2_Team_4);
 * Sure we can! It's for the greater good, or something... (_Conversation_3_NPCEnd_1);
 * Meh, we're just following orders. (_Conversation_3_NPCEnd_2);
 * Fine, we were done anyway. (_Conversation_3_NPCEnd_3);
 * So you're the ones messing with our little experiment... (_Conversation_3_NPCStart_1);
 * We transmit the sound of a barn owl screeching directly into the Settlers' brains. (_Conversation_3_NPCStart_2);
 * We then measure how quickly they turn against each other. (_Conversation_3_NPCStart_3);
 * And, yes, we know owls are extinct. We've trained parrots to mimic them. (_Conversation_3_NPCStart_4);
 * You can't experiment on Settlers without their consent. (_Conversation_3_Team_1);
 * Your scientific experiment is enabling superstitious beliefs. (_Conversation_3_Team_2);
 * We'll let you live if you give us the parrot. (_Conversation_3_Team_3);