Brendan Gall

Scientist who traveled to the Pegasus Galaxy with the members of the original Atlantis expedition. He and Dr. Abrams accompanied Dr. Rodney McKay and Major John Sheppard to investigate an Ancient weapons platform that had been discovered on Atlantis's sensors.

Sheppard, however, was more interested in the Wraith distress signal his Puddle Jumper was detecting from a nearby planet. After consultation with Dr. Elizabeth Weir the Jumper was rerouted to the surface. While investigating the inside of the Wraith cruiser Gall and Abrams discovered a Wraith commander that had awoke from hibernation. It pushed Gall aside and attacked Abrams, feeding off his life energy until he was a dead husk.

Gall was wrapped in webbing and taken to be fed upon later. After moving to a different part of the ship the Wraith fed upon him until he gave up information about their Puddle Jumper. It deliberately left enough life inside him to keep Dr. McKay occupied while Sheppard, now down to one man, went off to try and fight the Wraith. Gall, who had known McKay before this particular field expedition, found Rodney's opinion about self preservation had changed. He wanted to get into the fight to help the Major.

Realizing that's exactly what the Wraith didn't want to happen, and that Rodney's field training was not going to save him, Gall used the remainder of his depleting energy to take his own pistol and shoot himself in the head.