A comedy musical about a suicide pact sounds like a terrible idea. But think again – because this tuneful two-hander isn’t just well-judged and moving, it also tackles the toughest of topics in a way no other genre can. It stands up to scrutiny as a heart-melting musical, but its real purpose is to offer clear and salient advice for anyone who’s facing their own darkest hour. It isn’t at all melodramatic to suggest that – if you internalise its messages – at some unknown time in the future, they might just keep you alive.

The story begins with a solitary man on a bridge, singing about his plan to jump into the darkened waters below. But he’s not alone for long: a stranger arrives with exactly the same idea, and soon the two start talking. Both men are gay, and they find themselves connecting not just as lost souls, but as friends or even lovers. They decide, for now, to climb down from the parapet… yet their lives remain unbearable, and so they form the suicide pact of the show’s title.

Much of the humour – and a lot of the sweetness – comes from the unlikely alliance between two very different men. The first is lovable because he’s so completely normal; he’s well-behaved, endearingly reserved, and he’s gone to meet his maker in a practical Gore-Tex jacket. The other is a study in flamboyance, arriving at the bridge on an alcohol-induced high and demanding to exit the world in a flurry of excess. When the pair draw up a bucket list, their choices couldn’t be more different… yet both want, desperately want, to talk about things no-one else in their lives understands.

And that’s why this had to be a musical. No other genre gives characters such licence to tell us what they’re thinking and feeling, straight from the heart. The music has a simplicity which highlights the vulnerability at its core, while both performers – Ronan Radin and Jason Tully – sing with warmth and tenderness. And if at times it feels like it’s motoring towards a tritely redemptive ending, the final twist and resulting song might be all your heart can bear.

The real world, of course, doesn’t work like a musical, and it would be callous to suggest that those in the depths of despair just need to find someone worth staying alive for. But that’s not what’s happening here. The sweet and simple love story is just a standard trope; what matters is that they open up to each other, find a way to release the pressure that’s been bubbling inside. It’s blunt and urgent in its appeal to candour, yet it’s all done with lightness and humour.

There’s a lot of spoken dialogue, and perhaps there’s room for an extra song or two, but the real power of Suicide Pact lies between the music. The life-saving message is there, built into the very foundations of the plot – and they repeat it, subtly, over and over again. If you need to, if it helps, they say, then plan your escape for tomorrow. But talk about your feelings, and you’ll make it through today.