TRANSFORMERS: THE LAST KNIGHT 

What's it rated? PG-13

What's it worth? Nothing

Where's it showing? Stadium 10

Director Michael Bay (Bad Boys, The Rock, Armageddon, Pearl Harbor, Transformers) returns with this fifth—and hopefully final—installment of the bombastic series based on Hasbro toys about two Cybertronian races: the good Autobots and the evil Decepticons.

This time around, Autobots leader Optimus Prime (voiced by Peter Cullen) learns his home planet, Cybertron, is dead, and that he's responsible. He discovers he must recover an artifact from Earth in order to bring his planet back to life, but it will mean the end of Earth.

Meanwhile, Cybertronians on Earth—both Autobots and Decepticons—are being hunted and destroyed by the human-led Transformers Reaction Force (TRF), but Cade Yeager (Mark Wahlberg) still believes the Autobots are a force for good, and he works to save them as well as give Optimus Prime a chance to do the right thing even though he's fallen under the spell of his maker, the sorceress Quintessa.

For a guy who's known for big, dumb spectacles, Michael Bay has really outdone himself. This is the biggest, dumbest spectacle of all—oppressive, incoherent, obnoxious, but worst of all, boring. If it wasn't for all the intermittent explosions, I might have at least enjoyed a refreshing nap, but instead I was rocked from my slumber by one pyrotechnic display after another.

The film's opening sequence takes us back to 484 AD, where King Arthur (Liam Garrigan) and his army are facing insurmountable odds in a pitched battle. They're waiting on Merlin (Stanley Tucci, who seems to be the only actor involved who realizes how silly the whole thing is), who has promised to arrive with a magic object that will win the war. It's an alien staff Merlin receives from a Cybertronian whose ship crashed on Earth, where he's remained stranded and in hiding.

Fast forward to the present, where some kids have ventured into a Chicago no-go zone patrolled by TRF mechanical soldiers trying to kill Cybertronians. The imperiled kids are saved by 14-year-old Izabella (Isabela Moner), who in turn joins forces with Cade to save the Autobots. It turns out that Cade is "the chosen one," who receives a metallic talisman from a dying Cybertronian named Steelbane.

Wow, this really sounds absurd, and it is. The rest of the film is Cade, Izabella, random hot chick Vivian Wembly (Laura Haddock), upper crust British gentleman with all the answers Sir Edmund Burton (Anthony Hopkins), TRF commander who "gets" that the Autobots are good Colonel William Lennox (Josh Duhamel), and Transformers such as Bumblebee (voiced Erik Aadahl) and Hound (voiced by John Goodman) trying to save Earth from destruction as the planet Cybertron comes closer and closer to Earth, because apparently the laws of physics are not a thing in Transformers World.

Let's be honest: It's not like any of the previous four Bay-directed Transformers films have been good, but at least the first one—Transformers (2007)—was a bit more coherent and fun, plus it introduced Megan Fox to a sea of fan boys. She and Shia LaBeouf reteamed for Transformers: Revenge of the Fallen (2009), but they couldn't create the same semi-magic of the first. It's been downhill after that.

In Transformers: Dark of the Moon (2011), Fox was jettisoned for vapid blonde "it" girl Rosie Huntington-Whiteley and the goings-on headed in part to Earth's moon, increasing the dumbness to new heights. Mark Wahlberg joined the fray in Transformers: Age of Extinction (2014), a title I hoped spelled the end of the tiresome series, but Bay has proven time and time again that he can milk a bellowing CGI mechanical dead cow.

Review site Rotten Tomatoes is a pretty good indicator of how the franchise has slowly slid into irrelevance. The first had a 57 critic and 85 audience score, the second a 19 critic and 57 audience score, the third a 35 critic and 55 audience score, the fourth an 18 critic and 51 audience score, and this fifth one, a pathetic 15 critic and 56 audience score. If only around 50 percent of the audience likes these films, why do they keep going back for more? Stop encouraging Bay with your movie dollars! Sheesh! (149 min.)

—Glen Starkey