The Black Hand were a terrorist group that were plotting to assassinate Archduke Franz. They had been given weapons by a high official in Serbia's government. These men wanted to assassinate Archduke Franz Ferdinand because they didn't want Austro-Hungaria to rule over Serbia
I will never talk
The Archduke was scheduled to tour around the city of Sarajevo. This was when the Black Hand were plotting to assassinate him. They knew that he was out in the open and that he didn't have that much security as he was in an open top car.
The members of the Black Hand were positioned down one of the roads that Franz Ferdinand was going to drive down. Muhamed Mehmedbašić was the first conspirator that was ordered to throw a bomb at the Archduke, but he didn't throw the bomb because he believed that a police officer was too close to him so he would quickly have been arrested. Nedeljko Čabrinović was the next to throw one of the bombs at Franz Ferdinand he successfully throw the bomb but it bounced off the car.
The Black Hands Arms Dealer, also a leader in Serbia
The second Nedeljko Čabrinović throw the bomb police officers chased after him. His plan was to drink a certain poison and then jump into the near by river, this failed because the poison he had expired before he could use it.