First appears in "First Casualties." 

Malarkey is the nurse at the Veteran's Home who kept Bad Company drugged up. She later joined Bad Company, after they were branded terrorists, to act as their medic.

Her most intriguing act is later, after Mac was shot dead. She removed his brain to preserve it to put in another body later. *

Malarkey, along with her Bad Company mates, discovered the truth about how the Krool War started and when they tried to make it public, they were branded Terrorists by those trying to keep the truth hidden. They then set off on a mission to find proof of the conspiracy. Kano found the proof but kept it a secret so that Bad Company would remain together on a mission. 

Malarkey remained in Bad Company. The last we saw of her she was continuing on their mission to find proof of the Ararat War Conspiracy.

*One of the mysteries in this story is how is it possible for Thrax, Kano, Flytrap and Mad Tommy to still be alive? Could it be that they too had their brains removed and later put back into their own bodies?