Glee writer/co-producer Roberto Aguirre-Sacasa is working on a script for a third movie adaptation of the colourful stageshow, according to The Hollywood Reporter - and Gordon-Levitt is reportedly close to signing on as lovestruck hero Seymour.
The film has a history of big-name links - Jack Nicholson appeared in the 1960 version and Steve Martin portrayed a manic dentist in Moranis' 1986 movie, which also featured John Candy, James Belushi and soul legend Levi Stubbs as the voice of man-eating plant Audrey II.
Hosting Saturday Night Live, the young actor reprised Potter for a skit set in 2020, during which the former boy wizard was living off his past glories as he greeted new students.
Now unkempt and balding, the literary hero had fallen on hard times and was back at Hogwarts, boasting about how he vanquished Valdemort a decade before.
In the skit his friends, Hermione Granger and Ron Weasley, were Hogwarts teachers and Draco Malfoy was the parent of a new student.
The hilarious sketch ended with the news that Hagrid had wed Potter pal Luna Lovegood.
All the characters, apart from Potter, were played by SNL regulars.
Radcliffe also appeared as a lovestruck, ponytailed store assistant, the star of a knock-off Jersey Boys musical titled Delaware Fellas and the Yorkshire terrier pet of Casey Anthony, who was controversially acquitted of the murder of her young daughter in 2011 in various skits on the show.
The ABBA stage show became a box office phenomenon when it was transformed into a 2008 film, overtaking Grease as the world's top-earning movie musical after pulling in a mammoth $600 million (£400 million) in global ticket sales.
Following the film's success, Seyfried admitted she spread rumours of a sequel around Hollywood because she was desperate to return to her role as lovestruck Sophie.
But now the actress has conceded she will never play the part again - as film bosses would struggle to put together a new installment.
She tells Britain's Marie Claire magazine, "F**k no! That's never gonna happen. Like, what would they do? What would they write about? How would they get all the actors back?"