Anna first appeared in season 2 as a pastor and speech-writer. She later assumed a major role aboard the Behemoth in season 3 during its trip to the ring gate and the subsequent crisis.
Prax emerged in The Expanse's main plot in season 2 when his daughter Mei was abducted on Ganymede by Dr. Lawrence Strickland for his deeply unethical testing of the protomolecule on children.
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