The nurse tells Conan that she just remembered Eisuke had surgery for leukemia when he was young, raising the possibility Rena may in fact be his sister. Meanwhile, the FBI manages to narrow the list of suspects down to three patients: An old man with a broken leg, a man with a neck sprain, and a man with dorsalgia. Conan volunteers to secretly investigate them. After recording the three patients on a secret camera, Conan reports back to the FBI. In his meeting with the man with dorsalgia, Conan proved the man was not faking his symptom as he had difficulty bending down to pick up an object and was frantically fighting against a sneeze to prevent sending a shock wave to his back. The other two patients are revealed to be faking their symptoms. Conan reveals that he noticed the old man had a scar and swelling near his heart suggesting he has an artificial pacemaker. Since the pacemaker's function would be interrupted by cell phone waves, it rules the old man out leaving Rikumichi Kusuda, the man faking the neck sprain, as their culprit.