Richard Madden and Priyanka Chopra cast in Russo brothers' Amazon Prime series Citadel

The series, which is being executive produced by the Russo brothers, has been described as a “multi-layered global series.”

What this means precisely is still a little unclear, but it is understood that in addition to being a “US mothership” version of the show, there will also be several local language versions in countries such as India, Italy and Mexico – all tying into the main series.

Bodyguard actor Madden and Indian superstar Chopra are the first names to be attached to the project – with both set to appear in the US version.

Specific plot details, beyond the fact that the series will revolve around the world of espionage, are still under wraps, but the show is expected to be on a rather large scale – hardly surprising given Avengers: Endgame directors the Russo brothers’ involvement.

The writing team for the show includes Mission Impossible writers Josh Appelbaum and André Nemec, Jeff Pinkner (Venom), and Scott Rosenberg (High Fidelity).

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The project was first announced in the summer of 2018, with Amazon saying, “All of the local series are meant to enhance the entire entertainment experience and will be available for the viewer to deep dive into an imagined layered world.”