Granted, the upcoming - and purportedly final - entry into Fox's X-Men franchise has a laundry list of production problems to deal with, but its most basic, fundamental issue comes down to casting.
Sophie Turner was widely panned for her performance as a young Jean Grey in X-Men: Apocalypse, with many singling out her unconvincing American accent and generally flat approach to the material.
As such, Dark Phoenix focusing its narrative entirely on Jean is rather worrying, given that Turner has done nothing to prove she can carry a tentpole movie on her shoulders, or that she's even worked on getting the accent right this time.
Additionally the first trailer seemed to draw attention away from Turner towards the ensemble while only having her speak a few scant lines if dialogue.
Whether or not she's the absolute worst thing in Dark Phoenix or not, her performance could very well undermine the entirety of Jean's epic arc throughout the film, causing it to implode upon itself.
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