LN-73 was a protocol droid in the employ of Hesk Beldross, a Thaereian investor associated with Hutt droid producers, during the final years of the Galactic Republic
LN-73B was sent by Beldross to go to the moon Uffel, in the Cularin system, to obtain some droids. However, the droid became stranded in the moon's orbit, and only 50 years later, in around 32 BBY, was LN-73 finally knocked onto the surface by a debris storm. By this time, its master was probably long since dead, although the droid continued in its orders, with no way of knowing this and, in all likelihood, with its circuits having deteriorated considerably.
Once there, LN-73 succeeded in recruiting visiting tourists Nia Reston, San Herrera, Philinda and Nikolo, as well as their guide, Tret, in its attempt to gain control of the droid construction facility. In order to win these visitors over, LN-73 falsely claimed that HG-211, Uffel's head of security, had been corrupted. It then lied that the Heroes of Cularin had also been attempting to sabotage the factory, prompting the tourists to attack them as well.
LN-73 is armed simply with an ion blaster and vibro-hand, although its disguise is perfect - a droid among droids. It also has the capability to reprogram entire buildings, an invaluable tool in its subjugation of the Uffel facility. LN-73 was also equipped with shields and a self-destruct mechanism, as well as augmented sensors and the ability to speak in languages including Basic, Caarite, Bothan, Sullustan and Tarasinese.