(out of 4)

It will break your heart – but in the best possible way.

Let's get right to the point: Elegies: A Song Cycle is the most satisfying, fulfilling, beautifully performed piece of musical theatre I've seen in this city for a long time.

It officially opened last night at the Berkeley St. Upstairs Theatre (although I saw it at a preview), and if I were you, I'd book my tickets now. Because once word gets out about what an absolute winner this show is, the place should be packed every night.

Elegies: A Song Cycle delivers just what its title promises: 18 songs written by William Finn, which are indeed elegiac in the sense of being "a song or poem for one who is dead."

The only difference is that most formal elegies are solemn in nature, while many of these are ribald, joyful and life-embracing. Oh yes, there is heartbreak as well and if you can sit through the final half-hour of this 90-minute show without being dissolved in tears, then your heart, I fear, is made of stone.

Inspired by the 1998 passing of his mother, Finn began to write a series of songs that celebrated people who had departed from his life. They range from a devoted family of Korean grocers who fed him when he was young and poor, to a group of gay men who celebrated "an all-male Thanksgiving" together each November.

There are ornery songwriters he really didn't like, chicken farmers who read Jean-Paul Sartre and even some famous people like New York theatre giant Joseph Papp.

All the songs are witty and perceptive, written with that combination of rhythmic invention and melodic idiosyncrasy that mark Finn's work. At their wildest, they're almost surreal, but at their best, they're clearly sublime.

That takes us through the first hour and were the show to end then, you'd be tempted to pronounce it "offbeat and interesting."

But then Finn moves in for the kill – literally. He starts with a song called "Anytime (I Am There)," which is the call from beyond the grave of a young mother who died of cancer to her daughters. Then we're into a pair of songs about Finn's marvellous mother Barbara and her last day on earth.

And while you're still reeling from the force of that, you find yourself on the morning of 9/11, where a husband is trapped in one of the twin towers while his wife watches it all on the TV at home.

The amazing thing about Finn's writing (and the performers in this production) is that while they fill these sequences to the brim with emotion, they never spill over the edge into maudlin excess, over-emotionalism or sentimentality.

Discreet direction by Lezlie Wade and sensitive piano accompaniment by Wayne Gwillim are two ingredients that make this possible.

But it's the marvellous cast who deserve most of the kudos.

Barbara Barsky claims our focus most strongly, not only because she's playing the figure of Finn's mother, but also because she has a quiet dignity and reserved power that fill her songs with nobility time and time again.

Steven Gallagher is also doing amazing work, proving himself an actor capable of conveying the most subtle emotions and delicate shades of meaning, while also knowing how to nail us to the wall when the moment demands.

And the talented Thom Allison reveals a new maturity and control here. Without sacrificing any of his sardonic glee or deep-seated feeling, he's learned how to communicate them in a more minimalist way that is even more effective.

Newcomer Michael Strathmore makes an astonishing impression. For most of the show, he's called on to do the broad comedy and he delivers it with charm and style, using his youthful energy to its maximum. But when the chips are down, he suddenly takes you to places of deep pain with an effortlessness that is breathtaking.

And Eliza-Jane Scott rounds out the quintet by nicely providing some of the more offbeat comedy characterizations as well as some of the most intensely personal sequences.

The whole work has been designed by Sarah Melamed with utter simplicity against a background of flowing white drapes, and Paul Major lights everything with an understated skill that works well.

It's also wonderful to hear these actors sing without benefit of any amplification, letting their own vocal skills provide all the modulation we need.

Elegies: A Song Cycle may not be for everyone. If you're looking for a campy romp, an empty spectacle or pointless nostalgia, you won't find it here.

But if you believe that musical theatre is an art form capable of rousing you to both tears and laughter in the same evening, then this is the show for you.

"The living was the prize. The ending's not the story," sing the cast and they're right.

These songs may initially seem to be about death, but instead, they're ultimately all about life and how we should embrace it while we can.