Alison Steadman: I'm a little bit Pam, but more Candice Marie

She specialises in suburban social climbers, but feels closest to a character from the 1970s. Just as well, as her new role involves channelling ghosts. Andrew Johnson meets Alison Steadman

(JUSTIN SUTCLIFFE)

Alison Steadman does a great impression of a seal. She wrinkles her nose, holds her head up and sort of arfs to illustrate the only noise to break the silence when she found herself stranded on an ice floe.

The interview is over, the tape recorder switched off, and all of a sudden one of Britain's favourite character actresses is in anecdote mode, telling a long amusing story of a helicopter breaking down when she was off on an environmental trip for a charity called Respect for Animals.

She is great company – a riot – once the tape recorder is off. During the actual interview, however, she seems to diminish into a lower wattage version of herself, revealing only glimpses of the humour that fired some of television's most memorable characters: from the overbearing social pole-vaulter Beverly, in Abigail's Party, to Essex mum Pamela in the BBC's hit sitcom Gavin and Stacey.

In fact, at first, Steadman is reserved. She arrives late for our meeting in a café near her home in Highgate, north London. Smart in a black two-piece, she glances around cautiously as if meeting someone on a blind date.

It takes a while to adjust when she opens her mouth: no estuarine English; no Pam or Beverly, nor the childlike monotone of Candice Marie, from the other defining 1970s Mike Leigh TV drama, Nuts in May. Disturbingly, she greets me in something akin to Received Pronunciation.

Fortunately, she doesn't keep it up for long. She is, after all, a performer. Moreover, one with remarkable recollection of her lines, past and present. So when she tells the story of how she came to be cast as Pam in Gavin and Stacey she slips effortlessly into character.

"I knew Ruth [Jones] and James [Corden] who had written it because we'd worked on Fat Friends," she says. "They wrote one episode and sent it to me and asked me what I thought. As soon as I read the opening scene I knew I wanted to do it because the writing was so good. You're setting up characters. You've got Gavin and his mother. Gavin's come home from work and a lot of writers would do a scene like, 'Hello mum, you alright?' 'Hello son, do you want a cup of tea?'.

"Instead of that we got this: Pamela is lying on the couch with cucumbers on her eyes stretched out. Gavin comes in and says: 'You alright mum?' She takes the cucumbers out of her eyes and says: 'No, I'm not actually.' And he says. 'What's the matter?' And she says: 'I've just been watching the television. And a bear was crying because its little cub had died.' And Gavin goes: 'Mum, bears don't cry.' And she says: 'Gavin, I know what I saw. But never mind. Those steaks won't cook themselves'."

That's the opening of the first episode, broadcast nearly four years ago. She still has lines at her finger tips from Abigail's Party and Nuts in May which are both closing in on 35 years old. But she speaks about them with such familiarity that it soon becomes apparent that the characters haunt her, because they are part of her. Perhaps this is lucky as she is about to star in Noël Coward's Blithe Spirit, playing the eccentric clairvoyant Madame Arcati, who inadvertently summons the dead first wife of a novelist, much to the chagrin of her successor.

Her return to the stage is only likely to reinforce recollection of the gauche, flamboyant, monstrous Beverly, whose arrival in British theatre catapulted Steadman and her then husband, Mike Leigh, into the big time.

The play, which began life in the tiny Hampstead Theatre before being broadcast on the BBC, is a landmark of British drama, loved for its dissection of aspiring middle-class manners as well as Steadman's grotesque character creation.

So after all this time, is she not just a little tired of being asked about it? "It used to really get on my nerves," she says. "I used to think 'Can't I do anything else?' But as the time goes on you think: 'Actually, this is amazing.' And after 20 years you think: 'My God'. Of course I love it. I haven't seen it for years now but I see the odd clip because it is a good laugh."

Laughing, more like braying really, is a key component of her best-loved characters, as is their southern suburban world view. In truth, Britain's best-known Essex woman is actually a scouser. Though she studied at the East 15 acting school in Loughton, Essex, she came south aged 19 or so from Liverpool, where she was born the youngest of three daughters. Her father was a production controller in an electronics firm. As a child she'd wanted to be an archaeologist because she liked "digging things up" or an artist. She can paint a bit and likes making things out of cardboard boxes and toothpaste tube caps in a Blue Peter kind of way, but "when you see the professionals you think: 'No'."

"I can sing a bit, but I'm not good enough to be a singer. So acting really was the one thing I felt I could do, and people told me I could do, so I had a go."

At first her dream was to join the Royal Shakespeare Company – she actually threw a coin into the Trevi Fountain in Rome and wished for it – but meeting Leigh and her capacity for creating characters took her in a different direction.

Their relationship is well documented. She met the director in 1966, her second year at drama school. They married in 1973, had two sons, created some of modern drama's classics and split in 1995. Steadman now lives with her boyfriend Michael Elwyn, whom she met while filming a BBC drama series called No Bananas.

She is still friends with Leigh, perhaps the closest thing the British film industry has to an auteur, and does not rule out working with him again.

"I don't talk about our relationship, or private relationships, but I certainly would work with him again. It's just, a matter of when is the right time for both of us? We follow each other's careers all the time, we're still friends; he came to see Blithe Spirit the other night."

She also talks a lot about Leigh's devising process, in which the actors are expected to inhabit their character even when they're alone.

"So when I was getting Beverly together we based it on a woman I'd told him about, a woman who lived in Essex who was a bit of a manhunter. You put the character into a situation where they are on their own because we all spend time on our own, doing simple things, even something as simple as making a cup of tea, so you can begin to think: 'Would she take sugar in her tea or not? What time does she go to bed? What are her ambitions?'"

The process is so thorough that she says she could walk out of the door and walk back in as Beverly even now. "I'd be able to do it, or as Candice Marie. In fact I was talking about this the other day. Not so much Beverly, but I'd love to play Candice Marie again, 35 years on, just to see her life now, to try to be her like she is now."

In fact, she says that of all the characters she's played the naïve, sweet, hippy, childlike Candice Marie from Nuts in May is closest to her heart.

"I always wanted to play that character again and Mike always used to go: 'Oh, we've done that. We want to move on,'" she says. "I loved playing her so much. There's something about that character, that woman who's very self-contained in her world of poetry and song-writing and painting, and all that I just really loved. I think it would be interesting to see her now and imagine if she'd had a family. I imagine she'd had one child, a boy called Sebastian, and he'd be in St Ives doing pottery or something."

She chuckles at this and confesses that the character of Candice Marie is a little like her younger self: a writer of bad poetry and a "three-chord wonder" on the guitar.

"I slipped into that character very easily, into that world. One of the songs Candice Marie wrote" – she recites the lyric the character sings at the end of the play: "Black smoke, crisp bags, detergents in the river/ Cigarette smoke makes me choke, litter makes me shiver/ Use it up, throw it away, throw it on the floor/ I've no use for it anymore' is very much me and now I am a great campaigner for not using plastic bags and not using plastic. I'm a member of Greenpeace and have been for 40 years. In another life I wouldn't be Candice Marie, but I can see myself being a campaigner for this, that, and the other."

Which brings us to the ice floe and the broken helicopter. As time wore on, she became more and more agitated waiting for rescue. Fortunately, her son Leo was along on the trip to step in as peacekeeper. The story is pure Pamela: "He was saying: 'Look at me, mum. Now is not the time to shout. Mum, look at me. Now is not the time to shout.'"

'Blithe Spirit' is at the Apollo Theatre, London, from 2 March

Curriculum vitae

1946 Born in Liverpool to Marjorie and George Percival Steadman.

1955 Decided to become an actress, aged nine.

1957 Attended Childwell Valley High School.

1961 Joined the probation service as a clerical assistant, attended Liverpool Youth Theatre.

1965 Won a place at the East 15 Acting School in Loughton, Essex.

1966 Met Mike Leigh.

1969 Made stage debut as Sandy in The Prime of Miss Jean Brodie in Lincoln.

1972 Filmed Hard Labour, a BBC Play for Today devised by Leigh. They become a couple during filming.

1973 Married Leigh.

1976 Played Candice Marie in Nuts in May.

1977 Appeared as Beverly in Abigail's Party at the Hampstead Theatre, again devised by Leigh. It is later televised.

1978 First son, Toby, born.

1981 Second son, Leo, born.

1987 Nominated for Best Actress Bafta for The Singing Detective.

1992 Won Olivier Award for The Rise and Fall of Little Voice; won the US National Society of Film Critics' Award for Life is Sweet.

1995 Split from Leigh after meeting current partner Michael Elwyn; played Mrs Bennet in the BBC's Pride and Prejudice.

1999 Awarded OBE.

2000 Appeared in ITV's Fat Friends where she met Ruth Jones and James Corden.

2001 Divorced Leigh.

2007 Appeared as Pam in Gavin and Stacey.

2011 Plays Madame Arcati in Coward's Blithe Spirit.

Andrew Johnson