Like the 2017 movie “It,” director Andy Muschietti’s follow-up, “It: Chapter Two,” lives up to the strengths of Stephen King’s novel of the same name, by portraying how much power both childhood friendships and childhood trauma can retain into adulthood, even as it illustrates how to take power over those lingering fears, by recognizing how small they ultimately are.

One of the greatest strengths of 2017’s “It” was in the natural chemistry of its cast of child actors, who not only came across as real kids facing real danger, but also captured the earnest, bickering dynamic of actual childhood friends.

While the 1990 two-part ABC miniseries adaptation of “It” neatly divided the child and adult casts playing “The Losers Club” into two separate episodes, Muschietti leans more heavily on the narrative structure of King’s novel, by continuing to weave pertinent flashbacks of the kids into the modern-day scenes of the reunited adults.

This allows audiences to spend more time with a great ensemble cast of child actors. Sophia Lillis as tomboy Beverly Marsh, Finn Wolfhard as smart-aleck Richie Tozier and Jack Dylan Grazer as hypochondriac Eddie Kaspbrak all continue to deliver top-flight performances. It also highlights how good all the adult actors are at playing grown-up versions of those same characters.

Although the Chinese restaurant sequence, which serves to reintroduce the adult “Losers” to each other, soon turns nerve-wracking, it says a lot about the skills of the adult cast that I felt like I could have watched an entire “My Dinner With Andre” film about their characters catching up with each other in middle age.

Jessica Chastain is every bit as good as you would expect as adult Beverly, and James Ransome flawlessly mimics Grazer’s hilariously motor-mouthed neuroses as adult Eddie, but even with stiff competition from James McAvoy, who plays adult Bill Denbrough so effectively that he really does seem like he’s simply an older version of the grieving big brother played by Jaeden Martell, it’s Bill Hader as adult Richie who steals the show.

Between this film and HBO’s “Barry,” the former “Saturday Night Live” cast member has been absolutely killing it as a dramatic actor, and by the time his character was reduced to tears at the end, I was crying too, moved by the power of Hader’s expressions of emotion.

And the characters of bookish Mike Hanlon and milquetoast Stanley Uris, who received short shrift in 2017’s “It,” finally get a chance to shine here, with adult Mike benefitting from being played by Isaiah Mustafa, and some key flashbacks revealing the hidden strengths of Stanley’s character, both as a child and in how he responds to being asked to fulfill his childhood promise as an adult.

I have mixed feelings about a scene of anti-gay violence from King’s novel, omitted from the ABC miniseries, that makes its way back into the opening reel of “It: Chapter Two,” because while it’s arguably more relevant than ever, and it’s clearly intended to complement the overall narrative’s condemnation of bullying, it also contributes to a media pattern of only introducing gay characters to harm and get rid of them onscreen.

Of course, in any adaptation of King’s “It,” graphic and unjust violence are going to be huge parts of the story, and while Bill Skarsgård remains as sinister as ever in ramping up the slow-burn scenes of building fear as Pennywise the Dancing Clown, director Muschietti knows how to stage enough jump-scares that even a veteran horror fan like myself was repeatedly trying to leap back in my seat, as far away from the movie screen as possible.

All this, plus a pitch-perfect cameo from actual film director Peter Bogdanovich, make “It: Chapter Two” a must-see.