Wikimedia Commons/Citadel Prime Video TV Citadel's $300M spy thriller returns May 6. All 7 episodes drop globally, weaving in storylines from its canceled spinoffs. April 22, 2026 AceShowbiz - After three years marked by two canceled spinoffs, Prime Video's high-budget spy thriller Citadel is making a much-anticipated return with its second season. The first season of this ambitious series reportedly cost $300 million to produce, translating to an average of $50 million per episode across its six installments.