Morgan Katarn had recorded a message to his son Kyle revealing the location of the map to the Valley of the Jedi and the truth about Kyle's Jedi potential, and encrypted its content. Only WeeGee could decrypt it, though Rebel computer wizard Wires managed to decrypt it for Jan Ors so that the holorecording could be played in a very bad quality.
Shortly before the Battle of Yavin, a copy of the Death Star plans was obtained through a prison riot aboard the Death Star. Rebel prisoners managed to steal a copy of the Death Star plans and beam it to a Rebel cell stationed at a base on Polis Massa. These plans would be transferred to a holodisc, and this holodisc would play a key role during the subsequent Imperial raid on Polis Massa. When Imperial forces stormed a command room located further in the base, they retrieved the holodisc. After returning it to a captured communications center, they were forced to hold of Rebel forces for a couple minutes as the computer needed time to uplink the data to the Imperial network. During this, the Empire discovered that this holodisc was a decoy, but it did lead Darth Vader to the whereabouts of the plans, which were now in the custody of Princess Leia Organa aboard the Tantive IV.