First, as per the title of this post, there are no significant spoilers in the review that follows. Still, don't read on if you want a totally unspoiled experience of X-Men: Apocalypse, as it's difficult to say anything meaningful without giving away, or hinting at, at least something.
That was your last chance.
Second, with that much said, I loved this movie.
I can't recall when I last walked out of a cinema feeling quite so joyful and exhilarated. Despite the dark aspects throughout (relieved by some fun and humour), and despite the large-scale destruction portrayed in many scenes, X-Men: Apocalypse delivers in a way that will leave fans of its characters ecstatic. In my post yesterday, I linked to a YouTube review by Grace Randolph in which she spoke of the many scenes that will excite fans, all of which are earned by what precedes them and sets them up. She's exactly right. The ways in which the pay-offs are earned may be more obvious to X-Men fans than to some of the mainstream reviewers, but it's clear that Brian Singer and others involved in making X-Men: Apocalypse understand the previous films, and their source material, intimately. It's all cashed out as well as you could possibly hope. There's much fan service here, in the sense that there's much to get us cheering for the impressive showings given to beloved characters - but it's never an unearned style of fan service.
Some of the reviews from mainstream film critics have grumbled about using a villain such as En Sabah Nur, or "Apocalypse", who is a straightforward existential threat with no redeeming moral features. And yet, even he is portrayed - by Oscar Isaac - with considerable subtlety and theatrical chutzpah. There's also just a lot of plain old-fashioned comic-book fun in having such a powerful, almost invincible, utterly irredeemable villain for the good guys to punch at - generally with little effect even though they don't hold back. It's not as if the movie is short of more sympathetic villainous characters, including Magneto (likewise played with authority by Michael Fassbender) and (with a bit less motivation for their actions) the newcomers to the franchise's current sort-of-prequel trilogy: Storm, Archangel, and Psylocke. But there's actually something refreshing about having the totally destructive and megalomaniacal Apocalypse as the main threat.
While I don't want to reveal events (or even the themes), I can say that the standard of the acting is very high. James McAvoy is superb as Professor X, with a broad emotional repertoire. Michael Fassbender portrays Magneto as an agonised malcontent warrior gifted with enormous power (for those who care about such things - and don't we all if we're X-Men fans? - Magneto's power feats in this movie exceed anything that we'd previously seen from him). Fans of Storm will be relieved to hear that her portrayal by Alexandra Shipp is incomparably better - more dramatic, more persuasive - than Halle Berry's wooden performances. This has promise for the future, as Storm has never really thrived as a character in the X-Men movies. Sophie Turner is more than creditable as a young Jean Grey, much as I find it hard to look at her without seeing Sansa Stark from Game of Thrones. Hugh Jackman as Wolverine has a rampaging, totally fitting, cameo, while Evan Peters, as Quicksilver, steals the show in some spectacular scenes (one in particular).
I could go on, but the bottom line is that anyone who cares about these characters - or about any of them - will leave the movie happy about their portrayals.
That's something of a pleasant change, I should say, since a weakness of this franchise has been iconic characters who've not been well served by the scripts and by the actors portraying them. Storm is one obvious example; Emma Frost is another. In that regard, X-Men: Apocalypse has no obvious weaknesses unless you want to complain that the younger students at Xavier's school (Jubilee and others) don't get individual development.
If there is a real weakness in the movie from the viewpoint of X-Men fans, it's a certain amount of predictability to the plot, and of course some scenes have already been given away by the studio's promotion machinery (such as the killing of Magneto's wife and daughter, early in the movie, and Erik's subsequent renewed rage against humanity; but even this well-advertised part of the story is handled with originality, surprises, unexpected strength).
Some events may seem confusing or contrived to mainstream reviewers or, more generally, to filmgoers who are not immersed in X-Men lore. Overall, though, here's the score on X-Men: Apocalypse. This is a superb, emotionally satisfying ending to the film trilogy that began with X-Men: First Class. For my money X-Men: Apocalypse is the best X-Men movie to date and a candidate for best of all in the wave of contemporary superhero movies that began with the original X-Men movie 16 years ago. At this point, some professional reviewers don't seem to "get" it - but do not, under any circumstances, let that put you off!