Engineer and advisor to Dr. Elizabeth Weir at the Atlantis base. Grodin is British, holds a PhD, and is a scientist. While assigned to the Atlantus outpost in Antarctica, Grodin studied the Ancients' drone weapons. He was efficient and considerate, often taking Weir's needs ahead of his own.
A more than capaple technician with a good working knowledge of Ancient technology, he was also versed in wormhole physics. Grodin could frequently be found working on equipment in the control room.
When it became clear that Wraith hive ships were heading towards Atlantis, Peter Grodin, Rodney McKay, and Puddle Jumper pilot Miller flew to an Ancient satellite weapon and attempted to re-activate it. Although the weapon managed to destroy one of the approaching ships, the remaining Wraith forces returned fire and Grodin, trapped on board, was killed when the satellite was destroyed.
Rising, Part 1 - Grodin is among the travelers to the Pegasus Galaxy, eager to explore the new realm.
Thirty Eight Minutes - Grodin is part of the team assembled to figure out a solution to the stuck Puddle Jumper.
The Siege, Part 1 - Grodin goes on a mission to try and get the Ancient satellite working again, and pays the ultimate price when the Wraith attack.