Eugene O’Neill had an extraordinary life. He was an extraordinary playwright, winning the Pulitzer prize 3 times, seeing 35 of his 50 plays produced, and being awarded the Nobel Prize in literature in 1936. He lived through extraordinary pain, both physical and psychological. From a cracked and collapsing family, he saw addiction, alcoholism, depression, disease, death, paralysing regret – the list is never ending. Is it any wonder then, that he was capable of a play like A Long Day’s Journey Into Night? Holding striking resemblances to his own life, the somewhat autobiographical story is one of extraordinary misery. It is often referred to as ‘the saddest play ever written’, a claim that I sincerely hope is true, as if I ever see something sadder than A Long Day’s Journey Into Night, I’m not quite sure I’d survive it.

It’s 1912. James Tyrone (Jeremy Irons), much like O’Neill’s father, is a failed actor who seems to survive on nostalgia and whisky, and Irons fills him with a stale and tired regret. Lesley Manville is mesmerising as mother, wife and troubled morphine addict Mary Tyrone, and her restless ramblings are hypnotic. Like a shark that will die if it stops moving, she carries on and on, talking and jittering and fussing and fluttering, as thought standing still and being silent might prompt some excruciating self-examination.

Their eldest son Jamie (Rory Keenan) is a drunk, but perhaps the wisest of them all, and there is a sense that he is seeking ignorance to achieve bliss. His younger brother Edmund, played by Matthew Beard, is book smart, enjoys gloomy poetry and cynical philosophy, and is tragically stricken with tuberculosis, which only Jamie will acknowledge. Together, they make an unhappy bunch. They all need help, so much so that they are unable to help anyone else, making for tragic faring. As the play goes on, they continue to pick at and circle one another. There are moments of calm and understanding that spark hope for them yet, but they are fleeting, and we soon realise how irreparably broken they really are.

Laced with grief, A Long Day’s Journey Into Night is beautiful. Never have I seen the essence of human suffering, the inescapability of mistakes made, and the desperation for a better tomorrow, so stunningly articulated. I went into the theatre last night blind, familiar with O’Neill, but not with any of his work, and I’m glad I did – it knocked me for six. It’s a long slog at 3 and a half hours, but it’s what’s required to paint such a detailed picture, and in turn a lasting impact.

Richard Eyre’s production is a startling reminder that life can, sometimes, be so unimaginably hard. There are a few dodgy accents, a dreadful Irish by Jessica Regan and American forgotten entirely by Irons, but the rich dialogue barely gives us time to consider this.

O’Neill has immortalised an unforgiving account of his family in A Long Day’s Journey Into Night. To consider that even a fraction of the pain in this play is born from truth, is devastating, so much so that I want to forget all about the doomed Tyrone family – however, I don’t think I’ll be able to.

A Long Day’s Journey Into Night is playing at the Wyndham’s Theatre until 8th April. For more information and tickets, see www.longdaystheplay.com.