The cast of Avatar 3 did indeed film multiple movies at once, specifically the second and third installments of the Avatar series. Principal photography for both Avatar: The Way of Water (the second film) and Avatar: Fire and Ash (the third film) began simultaneously on September 25, 2017, in Manhattan Beach, California. This approach allowed the filmmakers to capture scenes for both movies during the same production period, which is a strategy often used in large-scale film franchises to maintain continuity and manage production costs efficiently[1].
By November 14, 2018, director James Cameron confirmed that filming with the principal performance capture cast for these two sequels had been completed. This means that the main actors, including Sam Worthington, Zoe Saldaña, Sigourney Weaver, Stephen Lang, and Kate Winslet, had finished their primary filming commitments for both movies around the same time[1][2]. Sigourney Weaver herself reported on October 29, 2018, that her filming for Avatar 2 and 3 was complete, reinforcing that the cast worked on both films concurrently[2].
After completing the initial principal photography, most of the filming for the next two sequels was scheduled to begin after wrapping post-production on the first two sequels. Live-action filming for Avatar: Fire and Ash and its predecessor resumed in New Zealand in early 2019. However, the COVID-19 pandemic caused an indefinite postponement of filming in March 2020. Despite this, visual effects work continued at Weta Digital in Wellington, New Zealand[1].
Filming resumed in New Zealand in mid-2020 after health and safety protocols were approved by the New Zealand government. James Cameron and part of the Avatar crew were granted special visas to enter New Zealand under exemptions for projects of significant economic value. The crew underwent a two-week government-supervised isolation before resuming filming. This made Avatar: The Way of Water and Avatar: Fire and Ash among the first major Hollywood blockbusters to restart production after pandemic-related delays. By September 2020, Cameron announced that 95% of Avatar: Fire and Ash had been completed, with filming wrapping in December 2020[1].
This simultaneous filming strategy is significant because it allows for a more cohesive storytelling experience across the sequels and helps manage the complex logistics of shooting in multiple locations with extensive visual effects. It also reflects the ambitious scale of the Avatar franchise, which involves intricate performance capture technology and underwater filming techniques that require careful coordination.
In summary, the main cast of Avatar 3 did film multiple movies at once, specifically the second and third films in the series, with principal photography starting together in 2017 and continuing through various stages until late 2020. This method was part of a planned approach to efficiently produce the sequels while maintaining high production values and continuity across the films[1][2].


