It's a term of endearment bestowed upon the 78-year-old star of television and cinema, who divides her time between the UK and NSW and who became an Australian citizen in 2013.

"My great friend, the actor Simon Callow, calls me a 'mad old bat'," Margolyes laughs as she chats to The Senior from her UK home.

So when it came to reprising her role as cantankerous matriarch Aunt Prudence in Miss Fisher and the Crypt of Tears - the first movie based on the Miss Fisher's Murder Mysteries TV series and Kerry Greenwood's Phryne Fisher novels - getting into role was a cinch for the veteran performer.

"I love playing Aunt Prudence. Her character is a little bit of the 'old country' in Australia. She is a bit of an old bat herself," says Margolyes, who received an OBE in 2002.

Set in 1929 and filmed on location in Morocco and in Melbourne's historic mansions, the film sees glamorous private detective Phryne Fisher (Essie Davis) and other Miss Fisher regulars return to the big screen, while taking fans on an exhilarating journey through exotic 1920s British Palestine to the opulence of grand London manors.

"Aunt Prudence's house was actually Ripponlea stately home in Melbourne. You cannot imagine how glorious it is to film in there."

The all-round funny lady, who is best-known for playing Professor Sprout in the Harry Potter movies as well as Sister Mildred in Call the Midwife, admits she had lots of fun with the Miss Fisher team.

"The production values really are very high, from the hair and make-up to costume and set," she says of the film, which was partially crowd-funded by Miss Fisher fans. "There is also something rather magical about the characters and the plot."

While the septuagenarian - who last year starred in The Lady in a Van at Melbourne's Playhouse as well as filming two documentaries - is not one to shy away from hard work ("2019 was exhausting") Margolyes is happy to leave the high-jinx crime-busting action to Davis.

But she has confessed she would like to play an "old lady detective" like Brenda Blethyn's raincoat-clad sleuth Vera.

"I'm terribly jealous of Brenda. I feel extremely strongly that I would like her to drop dead. But she is a dear friend so I don't really mean that. Mind you, Vera is very 'working class' and I think I sound much too posh for her."

Not one to shy away from touchy topics, Margolyes has also filmed TV series examining ageing around the world, including Indian Dream Hotel on Tour and Miriam's Deathly Adventure.

"I am interested in the process of getting old," she said. "Travel teaches you that we (westerners) don't always know 'the best way'.

"I don't think we treat our old people properly. They manage it much better in India, Japan and Vietnam."

But when it comes to her own retirement, Margolyes shows no signs of slowing down. "Retirement is when you die," she says.

"As long as people offer me work I'm going to do it."

The versatile actress can also be seen in the new film H is for Happiness based on the award-winning young adult novel, My Life as an Alphabet which was filmed in Albany, in WA's Great Southern. The film, also starring Richard Roxburgh, is out in cinemas now.

Margolyes will return to Australia for the Sydney premiere of Miss Fisher and the Crypt of Tears this month before spending time in Melbourne and then bunkering down in her NSW home for some much-needed R&R.

"I'm taking the rest of this year very slowly," she says. It will also be a time of reflection and to catch up with neighbours following the devastating bushfires that swept through the Southern Highlands.

"We survived, but it was very frightening and nerve-wracking. I wasn't in Australia, but my neighbours were wonderful. I felt very cut-off, but there was nothing I would have been able to do to fight the fire. Instead I tuned into the ABC."

Not one for holding back (the star dropped the F-bomb on live TV), Margolyes says she is "shocked and disgusted" by the current Australian government and climate change deniers who she says are "talking out of their bottoms".

"I love Australia - the country, the wildlife and the space - but I don't think we will recover from this."

Margolyes, who has worked and lived here for nearly 50 years, recently got to discover more about her adopted homeland for Almost Australian - a grey nomad adventure of a lifetime examining what it means to be Australian.

"One of the joys was seeing so many different parts of this amazing country," she said of the experience, which included visiting a remote Aboriginal community.

"It was bloody hard work, but also awe-inspiring. I slept under the stars and I was struck dumb - for once."

WE have 10 double passes to see Miss Fisher and the Crypt of Tears, released in cinemas nationally from February 27. To enter, simply fill in the form below.

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