Once a proud culture, Alebran's people were mutated by the Goa'uld Nirrti's genetic experiments. The former Goa'uld System Lord had discovered a piece of Ancient technology on the planet, and used it to manipulate their DNA to give them supernatural abilities -- including telekinesis and telepathy -- in the hopes of engineering the perfect host.
The unsuspecting people lived peacefully on their world when, for no apparent reason, they began to develop enormous growths of tumors and other bodily abnormalities. Then Nirrti revealed herself, promising to cure the population with the genetic manipulation device. However, she was hiding the real truth from them that she had originally been responsible for the outbreak of plague. Alebran, found by the S.G.C.'s Russian team, returned to Earth and informed Stargate Command that Nirrti had wiped out his entire village.
With the arrival of SG-1, Alebran's people defended Nirrti as their savior, using their abilities to imprison the team. SG-1 eventually managed to free themselves and convince Eggar, a local who had been transformed, that he should read Nirrti's mind to discover the truth for himself. The Goa'uld's plot was revealed and Wodan, another resident of the planet, used his telekinetic ability to kill Nirrti. Fortunately, Eggar had taken from her mind all that was necessary to operate the device that had transformed them, and began the work of restoring the population to normal.
Metamorphosis - SG-1's decision to release Nirrti catches up with them, as they must come to the aid of a world that has fallen prey to her genetic experimentation.