A leading man (Christian Slater) literally overacts himself to death on the Mojave Desert set of a murder mystery. And that spiritual Native American fella nearby? He’s wandered in from a stretch of Oliver Stone’s psychotropic sands, where Jim Morrison tripped on peyote and Natural Born Killers marked a high point in self-indulgence. Amazingly, Sir Anthony Hopkins has raised the bar to batshit insanity with this maddening passion project, which he wrote, directed, scored, and stars in with as much slack-jawed discombobulation as he’s likely to inspire in his audience. The synopsis suggests a Charlie Kaufman meta-riff on showbiz: While screenwriter Felix Bonhoeffer (Hopkins) bangs out said murder mystery, his characters start popping up in daily life, actors play themselves, dreams and reality bend space and time, blah, blah, it’s all in the mind. But who would have guessed that Hopkins’s brain was such an impenetrable inland empire? Not just nonlinear, Slipstream is a non-Euclidean freak-out of repeating sequences, excruciatingly long dissolves, superimposed Hitler footage, Dolly Parton look-alikes, ridiculous zooms, “We’ve lost the plot!” epileptic flashes, sepia-tone inserts, horizontal frame flips, now please let me off I’m going to be sick! Hopkins claims it’s a comedy, and perhaps John Turturro’s live-action cartoon of a mogul producer suggests so, but what does it all mean? That art can be just as shallow as Hollywood?