Heather Graham returning to Hangover III

The 42-year-old actress is set to reprise her role as Las Vegas stripper Jade - who married Ed Helms' alter-ego Stu in the comedy franchise's debut movie in 2009 - but plot details have remained largely under wraps. 

According to Variety, Jade looks set to reunite with Stu in the forthcoming movie, which will also see series veterans Ken Jeong (Leslie Chow) and Mike Epps (Black Doug) return for the third instalment. 

Lead characters Bradley Cooper (Phil), Zach Galifianakis (Alan) and Ed - who are collectively known as The Wolf Pack in the film - are also reprising their roles in the movie, which is expected to add a number of well-known actors in cameo roles, as well as the return of boxer Mike Tyson to the franchise.

The Hangover III is expected to return to its roots and be shot in Vegas, as the first movie was, with parts of the film featuring Tyson set to be filmed just off the city's famous strip at Caesars Palace Hotel and Casino. 

The motion picture is expected to see Phil and Stu attempt to break Alan out of a mental hospital and will be shot in Tijuana and Los Angeles.

Direct Todd Phillips will also return to the franchise and he is "so excited" to work on the third and final instalment of the series. 

He previously said: "I'm so excited to embark on another Hangover film with Bradley, Ed and Zach. We're going to surprise a lot of people with the final chapter we have planned.

"It will be a fitting conclusion to our three-part opera of mayhem, despair and bad decisions."