All things being equal, I am pleased that Home didn't turn out to be the movie to kill off DreamWorks Animation. I'd have been even more pleased if Home could have managed that feat while not sucking, but then, there had to be a reason why DreamWorks ended up on a cliff's edge in the first place, and it’s fun to believe that consistently churning out exhaustingly formulaic kids' films featuring ill-chosen celebrity casts and instantly-dated music cues could be part of that reason.

That being said, even by DreamWorks standards, the celebrities in this go-round are especially awful, and the music cues particularly distracting. It's unfortunate, because the bones of a stronger film are there. It looks pretty good: favoring a calm, pastel color palette mixed with soft lines and an old-fashioned, squishy approach to character animation, all of which goes a long way to mitigating what could easily be a grim and bleak scenario. The character design is a bit questionable, particularly the humans, but humans have been the Achilles' heel of DreamWorks/PDI animated features for as long as they've existed, and the ones in Home are no more stiff and soullessly robotic than the ones in Megamind or Turbo, and quite a great deal less so than the shuffling corpses of the Shrek films. The production design, meanwhile, is downright enticing, based as it is on an alien culture made up entirely of circles and curves, leading to plenty of smooth surfaces for the eye to glide around.

A pity, then, that Home ends up centering its lovely, if a bit simplistic world (it feels more than slightly like a collection of baby toys given life) on two of the worst performances in the annals of DreamWorks - the studio that has sucked every molecule of distinguishing personality from the voices of such diverse actors as Brad Pitt, Cameron Diaz, Michelle Pfeiffer, Ryan Reynolds, Angelina Jolie, Robert De Niro, and Tina Fey. There's quite a wide range of talent represented by those names, but all of them are better than Jim Parsons, noted for his role on one of contemporary television's most obnoxious comedies, and Rihanna, a pop singer noted for not being an actor at all (what she was up to in Battleship I shall not dignify with the rich history that attains to the word "acting"). To be strictly fair, Parsons's performance collapses as least as much because of the wretched things screenwriters Tom J. Astle and Matt Ember have arranged for him to say as because of the choices he made in saying them, but in both cases, the effect is about the same: it takes only a few lines to grow tired of both leads and their characters, and that leaves an awful lot of movie to spend in the company of a deeply unpleasant pair of protagonists.

The hastily pencilled-in backstory - treated infinitely better in last year's prologue short film-cum-stealth trailer Almost Home - is that a race of five-legged purple aliens about a meter or less in height, the Boov, have colonised Earth as part of their longstanding strategy of running like hell across the universe to stay away from a much more powerful species called the Gorg. Our story takes place on the very day that the Boov, having shunted all the humans on the planet to a reservation in the Australian desert, are ready to take residence in the vacated human habitations of the rest of the world. Naturally enough, in this species that fetishises conformity and impersonal behavior, one and only one Boov is a happy, optimistic fuck-up, and his name is Oh (Parsons). Oh will teach us many things over the course of the movie, the chief one of which is that the children's film plot where a main character doesn’t fit into his repressive society because he’s accident-prone and non-specifically "different" isn't getting any damn fresher. But anyway, Oh manages to cross paths with Gratuity "Tip" Tucci (Rihanna), perhaps the only human who didn't end up captured and sent to Australia, and who has since focused on tracking her missing mother (Jennifer Lopez, turning in a perfectly fine and completely anonymous performance). Along for the ride is Tip's curly-tailed cat Pig, who is, in fact, one of our better cartoon cats of recent vintage, and a clear argument in Home's favor.

The scenario and world Home creates beg for a more interesting story than the latest in an infinite chain of stories where two outcasts bond despite one of them being criminally annoying (I have not read the book by Adam Rex upon which the film was based, The True Meaning of Smekday, but I gather it to be that more interesting story). And even that musty old cliché deserves better than what Parsons and Rihanna throw at it: Parsons managing to be cloyingly sweet and horrifically smug simultaneously, while stressing all the lame comic awkwardness of the tortured Yoda-ese that the writers have whipped up for him. Impressively, it never recedes into the background, no matter how much we hear of it; every new line is a fresh hell. Rihanna, at least, is just vacant; flagrantly miscast as a 12-year-old with what must be a two-pack-a-day smoking habit in order to have such a low voice, the singer speaks lines that she twists into things that absolutely sound like what happens when the director says "you're mad! you think that something is funny!", so at the very least, she correctly indicates what our emotional response is meant to be, even if the rote way she gets there makes it inordinately hard to have that response. The biggest problem is that there are points where actual Rihanna songs are played diegetically in the movie, and Rihanna singing and Rihanna talking sound exactly the same, which raises the distracting possibility that this throaty tween is also a major pop star, or maybe that she just has a tape of herself that she listens to in the car. Neither of these possibilities answer the unforgivable writing conceit that her name is Gratuity and her nickname is Tip, but I can at least imagine that kind of affectation from a pop star in the real world. Incidentally, listening to Rihanna forces Oh to discover that Boov have an irresistible tendency to dance that they never indulge in, and if the movie seems to turn into a Doomsday countdown to a random film-ending dance party at this point, congratulations on knowing your animation studios.

Oh and Tip being such unendurable traveling companions, Home is fairly well doomed as an entertaining story. The writing isn't horrible for DreamWorks - potty jokes are kept to a minimum and pop culture references are limited mostly to a tedious pun on "Busta Lime" that the writers love so much that they keep having characters within the film laugh at it, even ones who have no in-world justification for having heard of Busta Rhymes - and the story is boring and predictable down to the smallest beats, but not meaningfully harmful. It's a tragedy that the film wastes Steve Martin on a small comic role as the Boov leader, but it's not like he was trying to do anything interesting or funny with the part. So it is, really and truly, a very ordinary film in almost all respects; but those leads! They're as ordinary as dental surgery, and more than enough to turn a simple, straightforward kiddie comedy with some pretty design and more fun animation than I'd have expected from this company into a gnashing grind.