The 44-year-old actor - who narrated an animated short film adaptation of the beloved fantasy tabletop role-playing game last month (May21) - now looks set to be part of the upcoming big screen blockbuster starring the likes of Chris Pine, Michelle Rodriguez, and Rege-Jean Page.
"After narrating the animated film, Benedict couldn't not be in the film version," a source told Britain's The Sun newspaper. "Filming has been in the U.K. too, so it was convenient for him travel-wise."
Cumberbatch is no stranger to the world of fantasy adaptations, having voiced both Smaug and Sauron in Peter Jackson's "The Hobbit" trilogy.
Meanwhile, "Dungeons & Dragons" - which is set to be released in 2023 - has been shooting on location at the likes of Wells Cathedral in Somerset, Alnwick Castle in Northumberland, and Carrickfergus Castle in Ireland where Rodriguez has been spotted on a scooter in costume on her way to the castle.
And earlier this year, it was reported Hugh Grant had signed on to play the villain in the movie.
At the time, it was noted that the plot of the movie - which will be written and directed by Jonathan Goldstein and John Francis Daley - and how Hugh's character will fit in is being kept a secret.
"Dungeons & Dragons" - now owned by Hasbro - was designed by Gary Gygax and Dave Arneson, and first published in 1974 by Tactical Studies Rules, Inc. (TSR) and is a tactical war game played out using mythical miniature figurines and platforms to create armies, kingdoms and weaponry and polyhedral dice and are used to resolve random events.