He suggests that the culprit may have left a message to establish an alibi .
Conan immediately notices that there is blood wiped from one of the buttons on the answering machine as well as blood on the doorknob .
Conan suggests that the culprit may have left a message to establish an alibi .
Conan immediately notices that there is blood wiped from one of the buttons on the answering machine as well as blood on the doorknob .