Antoinette was the XO of a USSA starcraft, while her husband was the captain.
When Jib Janeen, the Jupiter spy infiltrated the starcraft, it was reported that Janeen murdered her husband, Graymond Fontaine. Janeen was said to have then froze Antionette in carbonite and took on her appearance, pretending to grieve for her husband as a cover. After the captain's supposed murder, Sandy Manlius was given a battlefield promotion to captian of the starcraft, while his husband, Glenn, was promoted to XO.
The USSA presumed both Fontaines dead, and had a warrant out for Jib's arrest. Sparks Nevada and Croach the Tracker attempted to arrest Jib Janeen for his espionage and the deaths of the Fontaines in both Christmas on Jupiter and along with The Red Plains Rider in The Once and Future Thing, but Janeen evaded them both times.
In Quick! Change! it was revealed the both Fontaines were alive all along. They had left turned traitor to the USSA and were now working for Jupiter. Antoinette was head of one of Jupiter's largest spy corporations, while her husband taught espionage to children at spy camp. Antionette was now also acting as Jib Janeen's boss, and gave him a large promotion after proving he was a good parent.
- Those Jupiter Janeens - Quick! Change! (TAH #199)