Taking all that worked well in 2015's jaunty, good-humored "Ant-Man" while pushing it to the next level, "Ant Man and the Wasp" is the ideal elixir for viewers still grappling with the existentially weighty events of "Avengers: Infinity War." This consistently inventive sequel is goofy in spirit but treats its story and characters with the earnestness they deserve, a juggling of lightness and gravity aced by returning director Peyton Reed (2008's "Yes Man") and writers Chris McKenna & Erik Sommers (2017's "Spider-Man: Homecoming") and Paul Rudd & Andrew Barrer (2014's "Haunt") & Gabriel Ferrari. In terms of pure fun, this twentieth installment within the Marvel Cinematic Universe comes close to matching 2014's "Guardians of the Galaxy" and 2017's "Guardians of the Galaxy Vol. 2" at the top of the heap.

Former-burglar-turned-inadvertent-superhero Scott Lang (Paul Rudd) is three days away from completing his house-arrest sentence for assisting the Avengers and disobeying the Sokovia Accords. It should be easy enough—he has a drum set, a karaoke machine, and John Green's tearjerker novel "The Fault in Our Stars" to pass the time—but scientist Dr. Hank Pym (Michael Douglas) and Hank's daughter Hope Van Dyne (Evangeline Lilly) soon come calling after Scott experiences a sudden vision of Hope's mother, Janet (Michelle Pfeiffer), presumably killed thirty years earlier when she shrunk to a subatomic level and became trapped in the time-and-space-defying Quantum Realm. Hank has always assumed his wife was lost forever, but maybe not. When Scott went subatomic three years earlier and managed to return, it was all the hope Hank needed to dedicate his time to a machine built for traveling to and from the Quantum Realm.

In "Ant-Man and the Wasp," the actors and filmmakers work in perfect sync, most of them returning from the previous "Ant-Man" and already keyed into the jovial yet ultimately heartfelt tone of the series. If its predecessor was a necessary origin story, this continuation is freer to expand and explore the characters and their latest mission to save Hank's wife/Hope's mom from an irretrievable dimension. For likable ne'er-do-well Scott, who may be their direct link to Janet, his sacrifice could mean no less than extensive prison time if he is caught breaking his house arrest (the zanily clever workaround in keeping the police officers at bay and his ankle monitor active within his home is best left for audiences to discover). Additionally, two human obstacles appear in the forms of Sonny Burch (Walton Goggins), a shady tech guy, and Ava/Ghost (Hannah John-Kamen), a mysterious figure whose ability to phase through objects could eventually spell her demise. Both wish to possess Hank's portable laboratory and the inventions within (when shrunken, it ostensibly turns into a suitcase), the revolving door of hands the building falls into transforming the narrative into a sort of screwball chase flick of close calls and ticking timeclocks.

Paul Rudd (2016's "Captain America: Civil War") is an endearing hero, his Scott Lang more identifiable than the Thors and Tony Starks of the MCU because he's simply a blue-collar guy struggling to be a good father and make amends for his past mistakes. Stumbling into an opportunity to become someone who could potentially save the world may be dumb luck, but he comes to embrace this unexpected new calling and doesn't take it for granted. Furthermore, Scott's warm relationships with daughter Cassie (a winning Abby Ryder Fortson), ex-wife Maggie (Judy Greer), and Cassie's stepfather Paxton (Bobby Cannavale) are refreshing to see, a snapshot of a family of divorce who still manage to be friendly and supportive of one another. Rudd is a seasoned physical actor, and he gets to show off these gifts throughout; a scene where he shrinks to the size of a small kindergartner and must race around Cassie's elementary school to retrieve something valuable in her possession is hugely funny.

Given significantly more to do this time around, Evangeline Lilly (2014's "The Hobbit: The Battle of the Five Armies") is on fire as Hope Van Dyne, her Wasp alter-ego the very first female superhero featured in the title of an MCU film. This watermark is a long time coming (eleven years, to be exact), and Lilly is excellent in the role, sympathetic and strong, intelligent and savvy. Her drive to be reunited with a mother she hasn't seen since she was a little girl is the heart of the picture, while Lilly's surprising comedic talents are displayed in full force during a scene where she reenacts, "Drunk History"-style, a story told by Scott's fast-talking partner Luis (Michael Peña). Michael Douglas (2010's "Wall Street: Money Never Sleeps") is amiable and forthright as Dr. Hank Pym, unwilling to let his chance of finding his long-lost wife pass him by. And as Janet Van Dyne, the original Wasp, Michelle Pfeiffer (2017's "mother!") is a radiant addition to the cast; despite her character being quite different from that of Selina Kyle, it's impossible not to make the "Batman Returns"/Catwoman connection while watching her here.

With unmistakable tinges of 1987's Amblin fantasy-adventure "Innerspace" within its molecular structure, "Ant-Man and the Wasp" is whimsical and lighthearted but not inconsequential. The screenplay is rich in imagination and a shrewd purveyor of monkey wrenches, raising the stakes throughout without so much as a megalomaniacal villain in sight. Sure, Ghost and Sonny stand in our protagonists' ways, but they aren't typical one-note baddies with world domination on their minds. By and large, the people who fill the screen are relatable because they feel like regular people pulled into circumstances altogether more extraordinary than they could have ever imagined. Spending time with them is a treat. "Ant-Man and the Wasp" is bursting with dynamic special effects, skillful action, and a gentle human element that never gets displaced. Be sure to stay for the two end-credits codas, too; one of them is a game-changer, destined to have fans salivating all the more for next year's "Avengers: Infinity War" follow-up.