Going by the book: She knows we know she can sing; in Pam Gems' Piaf, she wants to prove she can act. Elaine Page interviewed by Edward Seckerson

Eva Peron changed her life; Edith Piaf has been waiting patiently in the wings. Elaine Paige shares more than just her initials with them both. Superstitious? Of course she is.

It's a long story. Paige was otherwise engaged with Peron when Piaf first came into her life. That was 1978. She never did see Pam Gems' play (or indeed Jane Lapotaire's award-winning performance). She read it, and she coveted it. But Gems had seen her - not in Evita, mind, but earlier still when planning a first production of Piaf at the Roundhouse. She and the producer in question caught a matinee of John Barry's musical Billy at Drury Lane, and both were knocked sideways by a diminutive actress with a powerhouse voice. 'Well, we've found our Piaf]' Gems recalls remarking, a little prematurely.

Twenty-one years later, Paige is at last under Piaf's skin, and the fit is good. The production photographs record a studied likeness - the tiny frame, the little black dress, the crucifix, the face of experience with its high forehead and narrow, expressive eyebrows. But it is just a likeness, a glossy one at that. Pam Gems' play is grittier. So is Elaine Paige.

She's fought for this one; she even bought the rights, just to make absolutely sure. Our first lady of the musical theatre wants the actor and not the singer in her to come first for once. Piaf is a play with songs, and Paige insists that she is an actor who happens to sing. We've heard that before, of course, from one Barbra Joan Streisand. But voices this good are eminently collectable: everybody wants a piece of them. Paige made her West End debut at the dawning of the age of Aquarius with Hair (1969); in Grease (1973) she wowed Richard Gere before he was fashionable; the tears have never really dried for the first lady of Argentina, and the memory of her faded feline, Grisabella (Cats), lives on in just one song.

Of all the singers who've sung it, none has matched Paige for uplift and intensity at that big modulation into the final chorus. When the voice really opens up at the top, the tone is so bright and focused and penetrating that it sounds just like a pure belt - straight from the chest register. It isn't, of course. And this is where we get technical. The trick, the skill, is in disguising the natural break between the chest and head voices: 'Whatever kind of singer you are, you should never be able to hear the gear changes. One voice - that's what you strive for. It's really a matter of strengthening the head register so that when you move from the chest into the head voice and start mixing the two, the quality of sound is just the same.'

At drama school, Paige's singing teacher heard operatic possibilities. She sometimes wishes she had gone that way: she has a passion for opera. One might imagine a small but perfectly formed lyrico spinto soprano. Not so: she was always more of a mezzo. So next time you hear her reaching for the stratosphere, remember her vocal centre of gravity is about an octave lower. Close friends and colleagues think she should try a few Country songs; sing low. And there is a kind of catch in the voice - just the hint of a Nashville twang. One of her most distinctive vocal mannerisms is the way she likes to tease with her portamento, the way she'll fall away from a note having just offered it. In that, she's just an old fashioned girl with an old fashioned ache in the voice. But if she chooses to rock it a little, the embellishments can be thoroughly modern.

But how much of the actor comes through in the singer? It isn't a voice of many colours, but rather shades of the same colour. There isn't the unpredictable and dangerous emotive charge of a Minnelli or a Streisand at full-throttle. 'I like to tell the story when I sing. Even if it's just a three-minute song with no particular context, I will have devised a scenario for myself; who is singing it, why, and to whom - to bring it to life for myself and, hopefully, my audience. The more one sings a song, the more detail emerges, the more it lives.'

Piaf's songs can only be lived. There isn't really a whole lot to sing, says Paige, and she's right. They all tend to gravitate around a handful of notes in the middlerange. It's the sentiments that sing. So will she even hint at Piaf's very particular vocal traits, maybe mix in a little of that tremulous, very indigenously French vibrato? Definitely not.

There will be no mimicry. 'But I have made the decision to keep the songs as far as possible in the keys in which she sang them, so that my natural middle voice will in a sense reflect hers. We both share strength in that middle register, and the rawness, the gutsiness of her singing is not a problem for me. But we could never sound the same. No two voices do - unless you are Rory Bremner.'

Piaf was very still on stage - maybe one telling gesture per song. But inside, it was life on the edge, and she held nothing back. The husky, morning-after voice tells you that neither does Paige. It's a hugely demanding role. But even greater than the physical challenge is the emotional one ('Peter Hall says it's like playing Hamlet, but you never get to England').

In her research, Paige went to Paris and followed as far as possible in Piaf's footsteps. Meeting Charles Aznavour was like meeting Piaf. 'Because he was never her lover - and I had to ask him - he was closer to her, and for longer, than anybody. Everybody sees this terrible, tragic, degenerate life. But she didn't see it that way at all. She had a ball; she lived hard and she lived fast.'

Material like Piaf doesn't come an actor's way too often. Top-drawer songs are elusive too. 'In the old days, the show songs of the day were more often than not the pop songs of the day. There's much more of a divide now between so-called 'show' and 'pop' music. And the great writers of the 'older' pop generation - like Elton John and Phil Collins - tend to keep their material for themselves.' So where does that leave a chanteuse like Paige? Probably filed away under 'Easy Listening' in your local record store.

There is a creative middle course. Benny Andersson, Bjorn Ulvaeus and Tim Rice found it with their musical Chess. Paige seized it gratefully. Now there's a score - one of the very best, and most scandalously underrated, of the 1980s - which managed to integrate musical theatre and contemporary pop worlds in a fresh and compelling way. When comes such another? For Elaine Paige, meanwhile, the 'Madama Butterfly' bathtime fantasies continue, and apart from a desire to add maybe half-a-dozen notes to her upper range, she has - in the words of that song - no regrets.

'Piaf' is in preview at the Piccadilly Theatre, Denman St, London W1 (071-867 1118)

(Photograph omitted)