Here are links to the previous two fan casts that feature any of the cast not shown below.
Part 1: http://www.comicbookmovie.com/fan_fic/news/?a=51223
Part 2: http://www.comicbookmovie.com/fan_fic/news/?a=51372
This synopsis is longer and more detailed than the other two, to which I may add more detail as well. The final part to this trilogy is World of the X-Men.
A few months have passed after the assassination of President Robert Kelly. The current president has led an international hunt for Magneto, who has gone into hiding since the day of the assassination. Genosha has plunged into a state of totalitarianism with Quicksilver as dictator. The island nation has been expelled from the U.N., and the façade of democracy is completely broken as the human slavery that has been occurring on the island since its inception is no longer being hidden. The president is threatening to declare war on Genosha unless Magneto turns himself in and the atrocities against humans on the island cease. Quicksilver is willing to help find his father, to avenge his twin sister’s death, so he asks Polaris to find him, but will not end human slavery on the island.
Angel and Iceman have quit the X-Men. The team consists of Cyclops, Jean, Wolverine, Storm, Colossus, and Nightcrawler. Professor Xavier sends Cyclops and Nightcrawler, who are joined by Beast (who has since undergone the transformation), to Genosha to persuade Quicksilver to end his reign and turn over control of Genosha to the U.N. Jean stays with the professor to help locate Magneto, and Wolverine, Storm, and Colossus are sent to stop a group of mutants calling themselves “M’s Brotherhood” from breaking in and destroying a government facility. There, they find Mystique, Avalanche, Pyro, and Rogue and a battle ensues. It turns out that the government facility is being run by Bolivar Trask, and had been running since the Kelly administration. The X-Men defeat M’s Brotherhood, but Mystique, Avalanche and Pyro flee, leaving Rogue behind. Trask informs the X-Men about the “Sentinel Initiative.” President Kelly ordered Trask to prepare a defence initiative to be used in the event of any mutant acts of terror towards the U.S. by Genosha. The X-Men return to the mansion where they interrogate Rogue, who is unwilling to divulge any information. Wolverine loses his patience, but Storm and Colossus suggest that they gain her trust first.
Mystique, disappointed with their performance, introduces them to a new member of their group who she believes will help them successfully infiltrate and destroy Trask’s Sentinel facilities. The mutant calls himself Gambit. Mystique sends Gambit to rescue Rogue from the X-Mansion before they strike again. On Genosha, Cyclops, Nightcrawler, and Beast discover a slave camp. Beast and Nightcrawler gather a group of sympathetic mutants to help liberate the camp, while Cyclops covertly inspects the camp. When Nightcrawler and Beast return with the other mutants, who are also joined by Havok, they defeat the mutants running the camp and liberate it. Quicksilver arrives, but is defeated and detained. Gambit breaks into the X-Mansion and fights the X-Men, who eventually subdue him.
Professor Xavier and Jean meet Polaris on Muir Island where they know Magneto is hiding. They find him and Dr. Moira MacTaggert in the medical facility where Scarlet Witch is being kept alive. Magneto informs them that it was not he who assassinated President Kelly, but Mystique who took his form. The professor, Jean, Polaris, and Magneto leave Muir Island and return to the X-Mansion to brief the others. Rogue finally tells them the location of M’s Brotherhood, and is granted a place in the institute by the professor. Before they all depart, the president declares that Sentinels will be sent to Genosha to “restore peace.” The X-Men, Magneto, Polaris, and Rogue go to Genosha immediately, and Professor Xavier intends to go to the central Sentinel facility to appeal to Trask to shut down the Sentinels. Gambit, who has decided to defect from Mystique, asks to join him. When they arrive, M’s Brotherhood is there, and they have already been destroying Sentinels. Mystique, in the form of Magneto, hurls a deactivated Sentinel at the professor, but Gambit saves his life. Xavier temporarily stuns Mystique (who later escapes), and he, Gambit, Avalanche, and Pyro look for Trask.
A battle between Sentinels and mutants rages on Genosha as Professor Xavier implores Trask to shut them down. After refusing, Xavier enters his mind, and discovers that the Master Mold controls the Sentinels. The professor instructs Gambit, Avalanche, and Pyro to find Master Mold and destroy him. The three mutants are successful, and the remaining Sentinels on Genosha cease to function.
One year has passed, Genosha is readmitted into the U.N., and Professor Xavier is the president and Beast is the vice-president. Magneto and Quicksilver are in prison. Scarlet Witch has woken up and is living in Manhattan (hint, hint). Havok and Polaris have rejoined the X-Men as reserve members, but are still living in Genosha. The whereabouts of M’s Brotherhood is unknown. Cyclops, Jean, Wolverine, Storm, Colossus, Nightcrawler, Gambit, and Rogue are outside having a picnic, as a largely-built man with white hair watches them from afar, looking particularly at Cyclops and Jean.
M’s Brotherhood—consists of Mystique, Avalanche, Pyro, Rogue, and Gambit who briefly joins the group.
Raven Darkholme/Mystique—Rhona Mitra
Nip/Tuck fans may remember Rhona Mitra from the threesome involving her character, Christian, and Kimber (and how could you forget). More recently, she was in Underworld: Rise of the Lycans (which to me isn’t the best example of her acting ability due to the nature of the movie, but her ability to be “active”). Nonetheless, Mitra is a talented actor, who would be more than suitable to play the mutant terrorist Mystique.
Dominikos Ioannis Petrakis/Avalanche—Dominic Purcell
I know that the character’s shorter in the comics, but Purcell’s height would make the character a little more menacing. As for the Greek accent, I don’t know if he could do one, but for this particular character, I’m not concerned about this detail.
John Allerdyce/Pyro—David Wenhem
David Wenhem appears to be a pretty versatile actor. Lord of the Rings, 300, and Jerry Springer: The Opera are just a few of his credits, so he’d be great choice to play a Pyro with a sense of humour.
Anna Marie/Rogue—Lyndsy Fonesca
I’ve watched Lyndsy Fonesca for a few years and she can play tough, feisty, sweet, and sexy, a few words which sum up Rogue quite well.
Remy LeBeau/Gambit—Ben Barnes
Ben Barnes is a very talented actor with a great sense of humour, and he also looks a bit like Gambit. For Gambit, the Cajun accent, or at least a Southern one, is essential, and I don’t doubt that Barnes would be able to pull it off.
Others
Bolivar Trask—John Slattery
I think that John Slattery plays uncompromising and slightly mad very well, so he’d be convincing as Bolivar Trask.
Dr. Moira MacTaggert—Catherine McCormack
I didn’t want a big name actor because the character’s role would be quite small, so I picked Catherine McCormack, who appears to be a decent actor.
Thank you to everyone who has been reading. I’m still thinking about whether I should do a second trilogy, given the way I ended this one. Feel free to comment, and if you didn't catch them at the top, here are the links to the two previous parts which have castings of the other characters who appear in the story:
Part 1: http://www.comicbookmovie.com/fan_fic/news/?a=51223
Part 2: http://www.comicbookmovie.com/fan_fic/news/?a=51372