After the disappointment of the most recent “Alien” installment, I almost sent this back unwatched, figuring I’d be wasting another 2+ hours feeling “Been there, done that.” So glad I didn’t. What a delightful romp. Check your brain at the door and let it happen. I couldn’t help flashing on Chris Morgan’s revamp of the “Fast & Furious” films with their emphasis on family (a theme that has carried the franchise into its 8th episode) because Vol. 2 here is all about family in its many varied forms. It is by turns funny, touching, cute, and relentlessly entertaining. Hardly a scene in its 135-min running time is wasted. (The opening credits were the weakest sequence.) Kurt Russell has a major role but Michael Rooker steals the movie. You can quibble about this and quibble about that, but from the git-go the film promises eye-catching sci-fi fun and that’s what it delivers.