Born in 2136, she served in then lieutenant David Anderson's unit during the First Contact War (2157) and was later assigned to the frigate SSV Hastings. She was still assigned to that ship in 2165, together with Anderson. Dah cuts a distinctive figure at 6' 3", and is known for her aggression and strong opinions that earned her the nickname 'Amazon', or 'Amy' among her fellow marines.
When the Hastings responds to the distress call from the research post on Sidon, Dah is assigned to Anderson's ground team and takes point during the mission. While escaping an underground room rigged with explosives, Dah is shot in the leg by a batarian mercenary. Anderson has to carry her back to the elevator; the two of them barely get out before the explosives go off. Despite horrible injuries to her right leg, Dah makes a full recovery and manages to recover enough to take in the view of the Citadel from the Hastings' bridge.