Note: The disks I have are in Japanese, without dubbing or subtitles. I only know about twenty or so words of Japanese, although many of those are words that are likely to occur in tokusatsu. The challenge I am setting myself is to see whether I can follow what's going on in these without knowing what's being said.
We start with what my disk set calls an "Intro Movie", although it's only about 25 minutes long.
Our Hero, who seems to be called "Yamashiro", is having a nap, and has a bad dream about being stuck in room. He hears a cry for help ("Tasukete!") and rescues his sister (Well, she calls him " oneechan", so I'm assuming she's his sister) and a kid (Nephew? Kid Brother?) from a gang of thugs dressed like Grey Bird-People (GBP). He switches to Spider-Man and fights them, but they literally vanish.
He is observed by Internal Dialogue Mustache Man (IDMM). Yamashiro gets a disturbing phone call, and then we see Spidey doing a lot of climbing. (Seriously, there are tons of climbing shots in this. Plus, the camera has a tendency to linger lovingly on Spidey's butt.) He breaks into a room, and IDMM is there. I believe IDMM is a cop - at least, he says "Interpol" alot. IDMM shows him footage of kids and young women at a pool. (I think IDMM knows Spidey's ID.) He also shows him footage of Fish-Headed Guy (FHG) firing torpedoes at a ship. I assume that IDMM has successfully recruited Spidey, as we see them shake hands. Spidey battles some GBPs, but it's a distraction as IDMM is kidnapped! Mystey Woman With Hat (MWWH) observes. Spidey finds a note stuck to a wall, which I assume is a ransom or a threat.