Ireland's most distinctive young character actress Evanna Lynch has just signed up to play a scandalous new role in whacked out true life crime drama Monster Butler.

According to the Irish Independent the 20-year-old former Harry Potter star made her name playing the ethereal eccentric Luna Lovegood. Now she is gearing up to play upper crust teenager Fiona Carrick-Smith, the daughter of an aristocrat.

In the film Lynch's character is seduced by her wise old butler who it turns out is actually an accomplished confidence trickster, in a role played by 68-year-old British actor Malcolm McDowell.

Monster Butler is based on the horrifying and nastily funny true life story of Roy Fontaine, who was also known as Archibald Hall, a bisexual jewel thief, con man and - unfortunately - serial killer.

Poor Fiona was beguiled by the dapper but entirely untrustworthy con man and their brief affair was destined to end in tragedy.

Monster Butler will tell the story of Fontaine's long and winding journey from petty thief as a teenager to a remorseless serial killer. When he died in 2002, he was the oldest person serving a whole life sentence in prison.

Birish acting great Gary Oldman has already signed on to play an arrestingly creepy taxidermist, who eventually becomes one of Fontaine's partners in crime.

Lord Of The Rings and Lost star Dominic Monaghan has been cast as Fontaine's young male lover and The Borgias' Joanne Whalley has also signed up for a role in the film.

The film begins shooting on location in Scotland and London this month.