The storyline in "Restart the Earth" is simplistic, so very, very simplistic. The movie's narrative requires absolutely no involvement from the audience. This is a movie where you just lean back, grab your drink and snacks and watch the predictable and generic movie unfold, whilst the CGI is ensuring that you find some enjoyment in the movie.
It just makes zero sense why a plant would know when people are about to do something that would spell the doom of the plant, and thus be able to track down the humans and attempt to thwart their plans. Lazy writing, sure, but makes for mindless entertainment.
I have to say that the writing in "Restart the Earth" had some of the most cringeworthy and downright disturbing dialogue I have ever stumbled upon. There was a scene where a soldier sits with a little girl, and the soldier says "If your dad was dead, you could be my daughter", and the girl's father is standing right behind the girl. That dialogue was so toe-curling that it was hard to witness.
I wasn't familiar with the cast ensemble in "Restart the Earth", but they definitely had some nice enough talents on the cast list, each actor and actress did a good job with her given role and character in terms of bringing the character and the storyline, however weak it might be, to life on the screen.
Sure, I get why the movie maker would opt to put in a growling sound when you see the plant's long tendrils skulking about, searching for humans. It does add a layer of thrill and excitement to the scene. But come on, seriously? A growling plant? Since when did plants grow vocal chords? It is just downright idiotic and sort of turns what would otherwise be an exciting scene into something laughable.
Visually, then I will say that "Restart the Earth" was good. The CGI rendered plants did, for the most parts of the movie, look realistic and were well-rendered and animated, bringing the plants and their stalks to life in a believeable manner on the screen, if you can abhor from the growling sounds. However, some of the scenes where the characters are moving through the overgrown city just looks downright horrible, you can clearly see that it is green screen, and it is difficult to unsee once you notice it.
A movie such as "Restart the Earth", which clearly is a special effects dependent movie, should strive to have the best of special effects and CGI effects to be properly functional and effective.
Watchable for what it was, "Restart the Earth" is a somewhat hollow movie experience held afloat by the CGI effects. My rating of director Zhenzhao Lin's 2021 movie lands on a five out of ten stars.