To premiere this summer, the show follows Halle Berry's astronaut character who returns home from a year-long solo mission in space and tries to reconnect with her husband and son in their everyday life.
"Her experiences in space and home lead to events that ultimately will change the course of human history," a synopsis said.
Gagnon, 8, will play Berry's son. His credits include "Looper," "A Friggin Christmas Miracle," "Wish I Was Here, Rio 2" and "Tomorrowland."
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