I saw this movie two months ago, which is to say this isn't going to be a super high-quality in-depth review. I write these reviews for fun, and I haven't been feeling the fun for the last few months.
Ant-Man is a Marvel Studios movie, and Marvel hasn't made a bad movie in the MCU era. Some have been better than others, but no outright duds. Ant-Man is a bit of a complicated property - the character has a long history in the comics but has never been popular outside the comic book community. Furthermore, he is best known for storylines where he abused his wife and was generally a terrible person.
Marvel took a very smart approach to this spider's nest by making the main character of the Ant-Man movie a brand-new character, and relegating Hank Pym to a secondary role as an old, retired Ant-Man. The script was co-written by Edgar Wright (Shaun of the Dead, Hot Fuzz, The World's End, Scott Pilgrim), who was also slated to direct until fairly deep into pre-production. The man who replaced him, Peyton Reed (Bring it On) did a competent enough job, but it seems apparent that most of the good parts are Wright's, and the not-as-good parts are the reason he left the project. Wright's style and humor infuse much of the film, to its benefit.
The basic plot is that Hank Pym's former protege and current CEO of Pym's company is a comic-book villain who wants to replicate the technology which allowed Pym to be the first Ant-Man, weaponize it, and sell it to the highest bidder. This is not a groundbreaking plot, but it serviceable. The new Ant-Man is a reluctant hero (Scott, played well by Paul Rudd) who is thoroughly unqualified to take the role. This is the weakest part of the plot - it's hard to accept him when Pym's daughter (Evangeline Lilly's Hope) is demonstrably more capable than him. The rest of the plot is about Pym's relationship with said daughter, and this is the part where the script was clearly doctored, and clumsily, to make that part of the plot come together, with imperfect results.
Much of the humor comes from Scott's trio of criminal associates, especially Michael Peña's Luis.
Ant-Man is an enjoyable movie with some annoying flaws. One of those was already touched on - the treatment of Pym's daughter Hope. Another is the underrepresentation of women in general. The only female characters worth noting other than Hope are Scott's ex and daughter, who have limited parts. I would have liked one or two of Scott's criminal sidekicks to be female.
Bechdel: Fail (C)
Mako Mori: Pass
What are these?