This sequel to the Paul Verhoeven movie is a huge disappointment, primarily because it lacks any intensity or suspense seen in the first two movies.
It's about a decade after the events of the first movie and we catch up with what's happened to Johnny Rico. Not a lot. He's fighting on a farm planet but it's taken over by the bugs and they narrowly escape but not before he's accused of treason. He's almost hanged but is spared at the last minute to head a rescue mission which involves a new weapon called Marauder, basically a variation of the exo-skeleton in ALIENS II.
The CGI special effects are a lot cheaper looking and while the gore effects are nasty there are simply too many heads rolling around, a distinct case where two heads--or twenty--are not better than one. There are two new types of bugs introduced, one that's a living grenade and another that looks like a giant scorpion, and that's probably the best part of the movie. There's also a huge brain insect that resembles something from the Lovecraftian mythos.
I think the biggest problem is that there's no further characterization of Rico and far too many of those military propaganda commercials that simply bring any flow of the movie to a halt. There's also this weird religious aspect to the script which just didn't work. All that praying only succeeded in giving actress Jolene Blalock an embarassing performance.
STARSHIP TROOPERS 3 can best be described as Cthulhu meets Jesus.