The Thor trilogy introduced viewers to the God of Thunder and his allies, the Warriors Three — but Fandral was actually recast over the course of the films, with Zachary Levi replaced by Josh Dallas. Marvel Studios has rightly earned a reputation for excellent casting, but in truth the studio sometimes switches things up. Sometimes this is because the relationship between the studio and the actors just didn't work out — as in the example of the Hulk and War Machine recasts. But a more subtle example can be seen in Thor's supporting cast.
In the comics, Thor has long been supported by a number of key Asgardian warriors who accompany him when he goes to war. Several of these heroes were adapted for the big screen when Marvel introduced Thor and Asgard, most notably the Lady Sif and the Warriors Three. "Surely you've heard the tales," Volstagg bragged when he remembered legends of their exploits. "Hogun the Grim, Fandral the Dashing, and I, Volstagg the Svelte." The Warriors Three continued to act as supporting characters throughout the Thor trilogy, and they were well-received by audiences — so much so the deaths of the Warriors Three in Thor: Ragnarok led to outrage.
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Volstagg and Hogun were played by Ray Stevenson and Tadanobu Asano in all three Thor films. In contrast, though, Fandral was actually recast after the first movie — only for the original actor to return for Thor: Ragnarok. In this case, the reasons were rather more practical.
Marvel originally cast Zachary Levi to play the part of Fandral, and the actor was delighted at the choice. Unfortunately, scheduling conflicts forced him to drop out, and he was initially replaced by Stuart
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