One-man cinematic conglomerate Robert Rodriguez adds cinematographer and production designer to his list of contributions to Spy Kids 3-D: Game Overthe third and, one suspects, final installment of the Spy Kids saga. Apparently having run out of missions for pre-pubescent secret agents Juni and Carmen Cortez (Daryl Sabara and Alexa Vega) and their spy parents (Antonio Banderas and Carla Gugino), Rodriguez reaches back two decades to recycle the plot of Tron, projecting his young protagonists into a virtual reality invented by the Toymaker, an evil genius plotting to control the world’s youth. Juni must rescue Carmen, trapped on the fourth level of the Toymaker’s overgrown video game. He’s allotted 12 hours and nine lives to do soand warned that the fifth and final level of the game is an unwinnable trap. Rodriguez’s screenplay is so arbitrary and its characters so skimpily developed that the movie lacks suspense and narrative thrust. But many of the visual effectsthe video-game simulationsare wildly imaginative and strikingly executed. Even if its cheap, primitive system for producing 3-D effectsin which two images, printed on a single film strip, are viewed through glasses with tinted lensesresults in murky colors and considerable eyestrain, kids will probably enjoy the film as an amusement-park-ride-like series of sensations. Grownups expecting the wit and winning performances of the original Spy Kids, though, will be sorely disappointed. The recurrent moral of the seriesthe primacy of familyis driven home this time out with jackhammer overkill. In this spirit, many members of the franchise’s acting family return, if only in roles tiny enough to classify as cameos. (These include Steve Buscemi, Alan Cumming, Bill Paxton, and Cheech Marin.) The introduction of one new cast member, however, suggests desperation on both sides of the camera: Sylvester Stallone, trailing clouds of cosmetic surgery and hair dye, plays the Toymaker. Apart from Jerry Lewis in the depths of intellectual pontification, I didn’t think there could be anything more painful that Stallone trying to be funnybut Rodriguez created sequences in which the Toymaker engages in debates with his three alter egos, also played by Stallone. Enduring quadruple mirthlessness through eyes teary from struggling to keep the film in focus falls outside the bounds of what most adults regard as entertainment. Joel E. Siegel