It starts with a creaky wooden door, a dimly lit interior, and a guide who speaks in equal parts history lesson and theater ...

How easy has it become for someone to build a deadly, and untraceable weapon? With nothing more than a 3D printer and parts ...

In the wake of Luigi Mangione’s alleged killing of a health care CEO with a partially 3D-printed pistol, we built the exact same weapon ourselves—and test-fired it.