A classic cartoon series is getting an animated makeover plus a never-before-told origin story. 

Scooby-Doo is a beloved cartoon series that was made into a live-action version in the early '00s. Now fans will finally uncover how the Mystery Gang came to be and how Scooby came into Shaggy's life. The series began in 1969 but continues to thrive. 

The new voices for the iconic crew are so accurate for the characters. Zac Efron will voice Fred, Amanda Seyfried is Daphne, Gina Rodriguez is Velma, and Will Forte is Shaggy. 

The nostalgic new movie does have a few critics already, though. Some think that the new Scooby doesn't sound like the original and they don't approve of the origin story's plot.

Watch the trailer here and get ready for the movie's premiere on May 15, 2020. 

Scooby and Shaggy meet for the first time on the beach and bond over their love for sandwiches, naturally. Then it's revealed that Scooby got his name from his favorite treat Scooby Snacks. Mark Wahlberg voices the villain Blue Falcon in the film. 

But some people are skeptical about the new version of the tale.

"I firmly believe that whoever made this has never actually seen an episode of Scooby-Doo," wrote one critic on Twitter. The origin story is a bit of a stretch when thinking about the various iterations of the cartoon series. But it's a new version for a different generation to enjoy. 

Some don't think Scooby-Doo needs an origin story.

"The harsh truth of it is that Scooby-Doo is just one of those stories that's better if you don't know the origin story. Don't tell me why these archetypes are detective friends and the dog talks I'd rather not know," writes another Twitter user. It's true that Scooby-Doo and the Mystery Gang have their own story, and how they came about isn't exactly necessary. Technically, in Scooby-Doo 2: Monsters Unleashed, we learn a little bit of the origin story from when the gang was in college. 

But the casting for Fred was totally on point. 

Zac Efron is the perfect amount of lovable jerk to play Fred, and I'd love to see him in a live-action version. "To the mystery machine! #scoob," writes Efron with a link to the trailer. Someone replied, "Actually can’t wait for this! Pure childhood nostalgia right now!!"

And Amanda Seyfried will make a great Daphne. 

Total dog-lover Amanda Seyfried has the perfect Daphne voice. "Jinkies! Scooby-Doo is back in this exclusive first look at the animated film ‘Scoob!’ The first trailer is coming this Monday," she reposted on Instagram. 

Even though many diehard fans are cringing at the new update, it's exciting for a new generation to see Scooby-Doo again. Hopefully, it sparks love for the original series and those bizarre early '00s live-action movies.