The first full-length animated Scooby-Doo adventure for the big screen is the never-before told stories of Scooby-Doo’s origins and the greatest mystery in the career of Mystery Inc. “ SCOOB !” reveals how lifelong friends Scooby and Shaggy first met and how they joined with young detectives Fred, Velma and Daphne to form the famous Mystery Inc. Now, with hundreds of cases solved and adventures shared, Scooby and the gang face their biggest, most challenging mystery ever: a plot to unleash the ghost dog Cerberus upon the world. As they race to stop this global “dogpocalypse,” the gang discovers that Scooby has a secret legacy and an epic destiny greater than anyone imagined. Starring in “SCOOB!” are Kiersey Clemons (“Neighbors 2: Sorority Rising,” TV’s “Angie Tribeca”) as Dee Dee; Zac Efron (“The Greatest Showman,” the “Neighbors” franchise) as Fred; Will Forte (“Booksmart,” TV’s “The Last Man on Earth”) as Scooby-Doo’s best friend, Shaggy; Jason Isaacs (the “Harry...