Holy crap, a great Dragon Ball movie out of nowhere!
What do you get when you take the plot of a gore-heavy sci-fi B-movie and put it in the world of Dragon Ball? You get a movie where a rich snob, basically Augustus St. Cloud from Venture Bros., challenges world-famous "hero" Mr. Satan to a duel as revenge for ruining his childhood, and then sics a bunch of ooze-covered bio-warriors on him. And then Broly comes back, this time in the form of a clone covered in ooze, and he looks like Swamp Thing.
This is everything I want out of an action-packed anime movie, and I had no idea I'd be getting it out of the, what, eleventh one of these stupid things? The movie is filled with fighting and action and danger but it's not all about one overly-powerful buff dude beating everyone up; instead, it focuses on the bizarre sci-fi elements, which includes a lot of gross-out horror with dudes getting melted by acid and stuff. Thankfully (sadly?) it's not graphic at all, and the movie is more geared towards the ridiculous humor of it all.
What kind of Dragon Ball movie has a cast like this? Our main heroes are... wait for it... Goten, Trunks, Mr. Satan, and... Android 18? Krillin makes an appearance too, but other than that, we don't have any of the usual cast coming in here and turning things into a monotonous punchfest.
Crazy good stuff, and I might recommend it even more highly on a rewatch. Since it's just 46 minutes long including credits, it's also a zippy-fast watch, and the first one since Dead Zone I can recommend with zero caveats. We've got a few more DBZ movies to go, and I have high hopes for Fusion Reborn based on my knowledge of it, but Bio-Broly could end up being the tops, and that's crazy.
As for the timeline, this is a direct sequel to the previous Broly movie, featuring some of the same plot threads and apparently taking place very shortly afterwards. It would also be set shortly before the Budokai Tenkaichi though Mr. Satan's prominent role makes it a bit suspect considering how shocked he was about having to duel one of these two kids during the tournament. Once again it can't be "canon" because of the Super Broly movie, but "canon" is stupid anyway.