X-Men: Dark Phoenix - 8 Mistakes It Must Avoid
5. Overstuffing The Roster
There's always the temptation to pack these movies with characters to ensure they're suitably epic, but Dark Phoenix needs to strike a delicate balance.
Sophie Turner and Tye Sheridan will be joined by series mainstays James McAvoy (Professor X), Jennifer Lawrence (Mystique) Michael Fassbender (Magneto) and Nicholas Hoult (Beast), and then there are the other returning Apocalypse actors.
There's also the fan-favourite Evan Peters as Quicksilver, while Olivia Munn is reportedly reprising her role as Psylocke.
Add newcomers to the equation - such as Jessica Chastain's Queen Lilandra (rumoured) and Scott Shepherd as Jean's father, Dr. John Grey - and the Dark Phoenix roster is beginning to rival Marvel's Infinity War.
The cast is growing by the day, and Simon Kinberg has to stop it spiraling out of control, because Jean and Cyclops's story will need all the screen time he can give it.