Definitely the weakest in the series...but alas...my favorite. The final human battle to take over what's left of the Earth is good. One major flaw in the actual battle is when the battle starts we see Aldo and his cavalry charge----then we don't see them again until the battle is over...throwing grenades in the bus. I had this film on Super 8 back in the seventies (the color 9 minute version) and it was a favorite of the neighborhood.