Stacy is a female CIA agent. She was in Tahiti when she had lost an earring with a microfilm somewhere on the beach. Johnny Westland hit on her while sitting in the Chi Chi Bar. They had an one-night stand but she had to leave early at dawn.
Later she participate in the Iceman operation, and John learned she is an agent during the briefing in the Pentagon.
John met Stacy in an oasis in Tunisia, and contacted her by saying "Iceman". She recognized him and gave him a amap, a fake ID and apartment key. She visited the apartment to check how things were going and saw John wearing a caterer's clothes. She reminded him to conceal his gun before going to rescue ambassador Richard Loyd.
Stacy waited him outside the terrorists' headquarters and shot the guards, allowing themselves to escape. She was present at the ceremony at USS Saratoga after which, she started a relationship with John.