'Fawlty Towers' star Prunella Scales is suffering from dementia.
The actress, who played hot-headed hotel manager Basil Fawlty's patient wife Sybil in the classic sitcom, has been struggling with the degenerative memory loss illness, her husband of 50 years Timothy West has revealed.
Speaking in new TV documentary 'Great Canal Journeys', he explained: "When you think this person that I loved and enjoyed this and that and the other with doesn't really exist anymore, that's quite painful.
"Prunella can't remember things very well but you don't have to remember things on the canal. You can just enjoy things as they happen - so it's perfect for her."
The More4 show follows the couple as they take four canal trips across the UK, enjoying the beauty of the British countryside.
Timothy, who stars as Stan Carter on 'EastEnders', admitted that while Prunella, 81, "doesn't really exist anymore", her sense of humour is still the same.
Prunella insisted the condition wouldn't stop her from acting and she intended to keep performing on stage.
She said: "I always say I want to die on the eighth curtain call. Eight will mean the show's been rather a success. I just hope I'm somewhere near the middle and have been reasonably good in the part."

Nicholas Hoult will star in 'Kill Your Friends'. The 'X-Men: Days of Future Past' actor will play an A&R agent in pursuit of the next big hit, in the film adaptation of John Niven's 2008 book of the same name, according to deadline.com. The 24-y...

Imogen Poots wanted to play a "redneck" in 'Need For Speed'.
The British actress was disappointed to learn she wouldn't need an American accent for her role as a young car dealer in Scott Waugh's action film where she plays Julia Maddon.
She told collider.com: "[Was it a relief?] Hell, no. I wanted to play like a redneck, but they wanted me to be British in the film, so I'm doing my best, but it's nice. I kind of understand that perspective too, because again, it adds something different to the film and again gives the characters more of an awkward beginning. They're not used to one another's culture or whatever it is. I can see their point of view for wanting to try that."
The 24-year-old beauty - who stars alongside 'Breaking Bad' star Aaron Paul and Agent Carter's Dominic Cooper - never felt intimidated being one of the only women on set as she was "taken care of" and insists the race-driving epic will appeal to women as well as men.
She explained: "It's a testosterone environment when we're making this film in, for sure. There's a lot of guys. There's a lot of lifting and a lot of cars breaking down and getting put back together again.
"But I think [women] will just go to see a fun movie. I don't think there's any divide whether you're male or female."

Lea Michele claims recording her debut album helped her to deal with the tragedy of losing her boyfriend Cory Monteith.
The 'Glee' star releases her record 'Louder' this month and says music has been her "therapy" but she still finds it difficult to listen to the track 'If You Say So', which is about Cory, who was found dead in his hotel room in Vancouver, Canada, in July last year, after an overdose.
Lea told Billboard: "It has both sides of the spectrum. Listening to it, it's therapeutic and difficult. It will always represent the most devastating thing that's ever happened to me in my whole life.
"But at the same time, music is therapy. It has been therapy for me in the entire grieving process and in my entire life."
The 27-year-old singer says she has to "acknowledge" what she has been through and claims another song on the record, 'Cannonball', represents finding strength and hope.
She said: "These are the two sides of my life right now. The grief, but also the search for strength and hope. I really wanted those two songs to bookend the album. Really let everyone know where I'm at."
'Louder' will be released on March 17 and Lea is already looking towards her second album after completing her debut last summer.
She said: "I'm already thinking about what I want it to look like. This record is such a strong representation of what the last two years of my life were like and I don't know what's next for me in my life. But I can't wait. Making music is so incredible, you tell the story of your life through music. I plan on it being very happy, very bright. Maybe not as dark."

Pharrell Williams believes the spirit of late soul singer Curtis Mayfield helped to make his song 'Happy' a hit.
The 40-year-old singer, who was nominated for an Oscar for Best Original Song for the track, which was used in the film 'Despicable Me 2', is a big fan of the 'Move On Up' singer.
He told the Daily Star newspaper: "I was pretending to be the masterful Curtis Mayfield. I hope he likes it, I'm trying to do what he would've done."
The song has conquered the charts and although Pharrell missed out on an Oscar, he is overwhelmed by his solo success, after big collaborations with Daft Punk and Robin Thicke.
He continued: "It's incredibly rewarding. I've never been so humbled in my entire life.
"It seemed like the most difficult thing ever, write a song for a mean-spirited character in the film who has this dry humour, trying to make him be happy."
The song is taken from Pharrell's new solo album 'G I R L', which was released this week, and he insists it's the "most important work" he's ever done, with his favourite track being another collaboration with Daft Punk called 'Gust Of Wind'.
He said: "It's my favourite because it's the first song that came to me.
"I've never had dreams about music before but I just woke up and I had it there.
"But those robots are so cryptic. they are like so 007 about everything."
Meanwhile, despite his solo success, Pharrell is adamant he's still with his band N.E.R.D, featuring Chad Hugo and Shay Haley, and they have been working on new ideas.
Asked if the band were parting ways, he said: "No, we're working on this animation project."

Britain's Prince William and Duchess Catherine will experience a white water ride during their time in Australia and New Zealand. The royal couple will embark on a 19-day trip next month from April 7 to April 25, along with their seven-month-old son,...

Sinitta is relieved she and Simon Cowell will never be subjected to romance rumours again now he has settled down and started a family.
The 'So Macho' singer, who is godmother to his newborn son, Eric, his first child with girlfriend, Lauren Silverman, is happy to be friends with the music mogul.
She told OK! Magazine: "The whole are-we-or-aren't-we thing with Simon and I ... Being a bit stuck or hung-up on each other, but not being able to fully commit to each other and equally not being able to fully move on ... In recent times we've finally been able to do that and him having a baby with Lauren certainly stops the yo-yo situation forever."
The brunette beauty thinks Simon, 54, has met his match with Lauren, 36, and feels they "deserve to be together" and be happy as a family with Eric, who was born on Valentine's Day (14.02.14).
Sinitta said: "Lauren has made my best friend extremely happy and he's finally found the woman he truly loves."
The 45-year-old singer, who dated Simon in the 1980s, admitted the TV mogul hasn't always been able to be a "faithful boyfriend" until now, but she insists he has been a "faithful friend" and she has a close bond with his mum Julie.
She said: "Simon and I have good times together. We care for each other's families. His mum's like my mother. I've known her since I was a teenager, we're old family friends."
Sinitta also addressed rumours that Simon, who is godfather to her children, gives her a wage, claiming she earns her own money but says he is generous when it comes to her son Zac, seven, and daughter Magdalena, eight.
She said: "When I was mentoring [on 'The X Factor'] he paid me the going rate. As godfather he pays towards my children's school fees and he buys us lovely birthday and Christmas presents. He's a generous friend but I earn my own money."

Celine Dion's husband has been battling throat cancer.
The 'My Heart Will Go On' hitmaker has been supporting René Angélil, 72, after he underwent surgery on December 23 to have a tumour removed, and the couple are relieved the operation was "successful".
Celine's representative told E! News: "Putting to rest rumours that have been circulating these past few weeks, Rene Angelil's office confirmed today that he has been recovering at home in Las Vegas following surgery to remove a cancerous tumour from his throat on December 23rd.
"The procedure was successful and Mr. Angelil was released from hospital a few days following the surgery."
René - who has grown-up children Patrick, Jean-Pierre and Anne-Marie from his previous marriages, and René-Charles, 13, and twins Eddy and Nelson, three, with Celine - has taken a break from his career managing his 45-year-old spouse to focus on his recovery and relax with his family.
The representative added: "During his recovery, Mr. Angelil has decided to take a short hiatus from his normal work schedule, and concentrate on rebuilding his strength through proper rest and nutrition."
Celine - who has a residency in Las Vegas - issued a statement which added: "I don't want René to stress out with work-related issues. I want him to focus on getting back to 100 percent. I've been doing my shows at the Colosseum and everything's under control.
"At home we've been spending a lot of quality time with the family. We feel very fortunate that we've been able to get the best care possible and we thank God every day for helping us to get through this ordeal."
René previously battled throat cancer in 2001.

Cate Blanchett slept with her Best Actress Oscar.
The 'Blue Jasmine' actress - who won Best Supporting Actress in 2004 for her role in 'The Aviator' - joked she and husband Andrew Upton had had a "threesome" following the Academy Awards on Sunday (02.03.14) because she couldn't bear to let the statuette out of her sight.
She said: "It's the closest my husband and I have ever come to a threesome."
The 44-year-old beauty - who has sons Dashiell, 12, Roman, nine, and Ignatius, five - with Andrew - admitted accepting the award was a bizarre experience.
She explained: "I was so stressed. I don't think I drank that much last night but it was such a release of adrenaline."
Cate appeared on Ellen DeGeneres' talk show just hours after the ceremony and admitted to the host - who had presented the awards - that she had only had "a little bit of sleep".
Ellen said: "What can I get you? I have Visine, I have Advil. I have water. I have a banana."
The actress replied: "Do you have a blanket or a coffee or something?"
Ellen had arranged to have pizza delivered to the A-list audience at the Oscars, but Cate had to stop for food on her way home because she was away from her seat when the pies were distributed inside the Dolby Theater in Hollywood.
She said: "I went to the bar to try and get something to eat and then they wouldn't let me back in!
"But all those actresses were hovering it up so I wouldn't have got a piece anyway."

Nigella Lawson has posed make-up free for VOGUE.
The curvaceous cook has landed her first magazine interview since she was forced to admit to previously snorting cocaine and smoking cannabis while giving evidence in court against her former aides Elisabetta and Francesca Grillo last December, when they stood trial accused of £685,000 credit card fraud.
The 54-year-old star appears fresh-faced on the British magazine's cover wearing just a hint of blusher and mascara, with the help of a "little retouching" from the art team.
Nigella said: "I was terrified of being photographed without make-up, and I hate having my looks talked up. It always makes me feel I'm going to be a disappointment in the flesh."
The magazine added: "Miss Lawson received a little retouching as we do with all cover images. Oddly given that she is a woman in her fifties, less than some people decades younger."
The TV chef - who currently stars in new Channel 4 cooking reality show 'The Taste' - also hinted at plans to branch out from cookery in the future.
She said: "I love what I do, but there are other parts of my brain that I haven't flexed."
The domestic goddesses, who is a long-time contributing editor for the fashion bible and initially wrote a cookery column in 1995, is set to discuss her traumatic ordeal in the tell-all interview.
Not long before her drugs scandal, Nigella's marriage to art collector Charles Saatchi came to an end in July 2013 after 10 years of marriage, just weeks after pictures emerged of him with his hand around her throat in a London restaurant.

Sarah Harding thinks Kimberley Walsh will be a "bossy mum".
The Girls Aloud star announced last month that she is expecting her first child with boyfriend Justin Scott and her former bandmate believes she will be quite strict in comparison to new mum Nadine Coyle, who had a baby daughter just a few weeks prior to Kimberley's announcement.
She said: "We were all shocked that Nadine was the first because we thought it'd be Kimberley. I think Kimberley will be the bossy mum, whereas Nadine has that LA thing going on."
While the 32-year-old star hasn't seen Nadine - who lives in Los Angeles with her NFL player boyfriend Jason Bell - since she gave birth, Sarah says the Irish singer is having a fairly easy time as a new mother.
She revealed: "I haven't met her baby yet, but she's getting on very well, surprisingly! She's really laidback, and so is the baby - she sleeps through the night. She must have had a chilled-out pregnancy to have such a chilled-out baby!"
Sarah, who is in a relationship with DJ Mark Foster, admits she isn't ready for children herself as she wants to focus on her music career.
She added to new! magazine: "I'm very focused right now and so is Mark. I'm not going to deny that I'm 32 - I'm embracing that fact. But my mum was in her late thirties when she had me and I think a lot of women are dominant in the workplace these days."

Brad Pitt never thought he'd win an Oscar.
The actor, who picked up the award as a producer for Best Picture winner '12 Years a Slave' on Sunday night (02.03.14), insists he never dreamed of winning and doesn't know what to do with his golden statuette.
He told E! News: "I don't know where I'm going to put it", adding, "I never thought I'd take one home, so I haven't thought that far in advance."
The 50-year-old star thanked all those responsible for making '12 Years a Slave', which tells the story of Solomon Northup who was sold into slavery, including director Steve McQueen.
In his speech, Brad said: "Thank you all for this incredible honour you bestowed on our film tonight. I know I speak for everyone standing behind me that it has been an absolute privilege to work on Solomon's story. And we all get to stand up here tonight because of one man who brought us all together to tell that story. And that is the indomitable Mr. Steve McQueen."
Brad also starred in the film and actor Chiwetel Ejiofor, who plays Solomon, previously praised his colleague.
He said: "I think the truth is we wouldn't have been able to make this film without Brad Pitt, because of what he brings.
"He's a movie star. He's a huge figure in this profession, in this industry."