International regulations about the safety of ships at sea require every modern vessel to be equipped with a Voyage Data Recorder to assist investigations in the event of an accident. As such, these devices are the primary means for acquiring reliable data about an accident involving a ship, and so they must be the first targets in an investigation. Although regulations describe the sources and amount of data to be recorded, they say nothing about the format of the recording. Because of this, nowadays investigators are forced to rely solely on the help of the builder of the system, which provides proprietary software to “replay” the voyage recordings. This paper delves into the examination of data found in the VDR from the actual Costa Concordia accident in 2012, and describes the recovery of information useful for the investigation, both by deduction and by reverse engineering of the data, some of which were not even shown by the official replay software.