Apprenticed to Jedi Knight Crian Maru, Vandap undertook the mission of tracking down one of the Brotherhood of Darkness' most ferocious warriors, Kaox Krul—the Madman, the Marauder, the Dark Killer. Traveling to the Balowa system from the planet Harpori, Dree and her Master believed they had a lock on Krul. However, the Marauder was able to get the jump on Dree and Crian and blasted their ship, damaging it beyond repair and sending it on a doomsday decline to the forested planet below. However, Dree and her Master were also able to damage Krul's ship, sending it plunging to the planet as well.
Dree and her Master survived the crash, but were now at the mercy of the planet—and worst of all, at the mercy of Kaox Krul, who had survived his landing as well. Dree and Crian surmised that they needed to put some forest between them and the Madman so as to keep ahead of him. However, as Crian was preparing the ship's speeder bike that had survived the crash, Krul was upon them. Dree was forced to engage him in battle but was rescued by Crian who snatched Dree up onto the bike as she sped past the fray.
Zooming into the forest, the two Jedi thought the bike would help them put some distance between them and Krul. However, Krul opened himself up to the power of the dark side, using it to give him incredible speed and allowing him to keep up with the bike. Slashing out with his lightsaber, Krul cut cable lines causing the bike to slowly lose power. However, Krul's swipe also caused him to lose his footing, sending him crashing into the ground and allowing Dree and Crian to escape, at least for the moment.
For two days afterward, Dree and Crian were able to elude Krul, but eventually he caught up with them. The showdown came one night when Dree awoke alone in a makeshift hideaway in a forest cave. Following her senses to a lake located in the middle of the forest, Dree found her Master standing at the shore. Without warning, Krul appeared and attacked Dree's Master. Dree watched as Crian traded strikes with the Dark Killer, and Dree watched and saw her Master start to lose ground against him. Feeling her master needed help, Dree joined in the battle and forced Krul into a two-on-one fight.
However, Krul was more than up to the challenge and took on the two Jedi. Although Dree and Crian were both strong in the Force, Krul had fully opened himself up to the powers of the dark side. Sending Crian flying into the lake with a powerful Force blow, Krul launched himself up and over Dree, landing behind her. Before Dree had a chance to react, Krul ran her through with his lightsaber. Before the eyes of her Master, Dree Vandap fell and became one with the Force.