John Heffernan’s extraordinary performance as the central and titular character in Tom Morton-Smith’s radiant and absorbing new play, Oppenheimer …. No one here gives anything other than a first-class performance. John Heffernan, in the central role, with the bulk of the play squarely on his shoulders, is world class. He is magical, mercurial, magnificent. ……. Heffernan explores every aspect of the man behind the mind, in minute, intricate detail,…. His eyes are remarkable: sparkling with knowledge, twinkling with humour, reflecting rage and disbelief, hollow and haunted by regret and the possibility of failure – the spectrum of total emotional involvement is all-consuming. ………. Heffernan knows how to use his voice to great effect, and there is real beauty in many of his Oppenheimer speeches. ……..a moment of sheer theatrical perfection that will be long remembered. His final speech, etched in tragedy, regret and fear, is stunning. ………..What is particularly exciting and insightful about Heffernan’s performance here is that he allows the audience to learn as much about Oppenheimer’s character from how Oppenheimer reacts to his associates, family and friends as they do from how or what he says. Even when silent, Heffernan is beyond expressively eloquent. britishtheatre.com
There is something in John Heffernan’s touching portrayal of the man behind the atom bomb known as ‘Oppie’, that reminds me of James Stewart. The slow American drawl, the dry humour and intense, raw emotion – not to mention the 1940s suits, and pipe. The actor really does a brilliant job of humanising the chain-smoking theoretical physicist with a complex love life, who led the Manhattan Project at the Los Alamos Laboratory in New Mexico, and ends up a broken man with “blood on his hands”. coventrytelegraph.net
John Heffernan as Oppenheimer is superb as he struggles to shake off his past to concentrate on becoming the first to create this terrifying weapon. To watch him perform is gripping and an emotional rollercoaster throughout. eeveelife.co.uk
Heffernan’s performance is superb: affable and charismatic yet slightly aloof, as the play wears on he retreats further into his core, his stare increasingly distant. Around him spin scientists, friends, families and women — some of whom become casualties as his priorities split and clash. ft.com
At the heart of this play is an intriguing performance from John Heffernan whose J. Robert Oppenheimer is a complex, introverted and often contradictory man. huffingtonpost.co.uk
Oppenheimer himself, brilliantly brought to life in all his complexity and contradictions by John Heffernan. legacygloucestershireecho.co.uk
At its core is, of course, Oppenheimer as a character – mercurial, charismatic played with a wonderfully steady focussed attention by John Heffernan whose Edward II at the National two years ago should have taken him to the front rank. He is an actor of intense, quiet inner truth. He doesn’t parade his talent but is very much in the Stephen Dillane school of introspective brilliance – now and again so much so, the voice drops to a husky whisper the meaning of which must have eluded even those sitting in the very closest proximity of the Swan londongrip.co.uk
Oppenheimer – brilliantly played by John Heffernan…….it was an interesting play, and John Heffernan, as Oppenheimer, was an amazing presence on stage. mcelhearn.com
Friends, relatives, lovers and dearly held Communist principles all have to be sacrificed to the grinding might of the US military machine and Heffernan, in a towering central performance, takes on an increasingly haunted look as he comes to realise the terrible implications of his achievement. standard.co.uk
Oppenheimer is John Heffernan in the performance of his career: riveting, truthful, complex, sinking deep into himself or flashing sudden charm. theatrecat.com
John Heffernan plays Oppenheimer convincingly, with distracted angularity and a look, early on, as if savouring a taste – secret knowledge. Yet by the end he confesses to dropping a “loaded gun in a playground”. theguardian.com
In the Royal Shakespeare Company’s production, the play hands John Heffernan, one of Britain’s best young actors, a role to match his talent, as the American physicist grapples — devastatingly — with the enormity and inevitability of his part in history. variety.com
In the person of dextrous John Heffernan, he is charismatic, optimistic, progressive, cultured and self-assured. ….. That Oppenheimer emerged from the historic mangle damaged, yes, but wise and unbroken is a tribute to his inner core of iron and, in this production, to the Herculean efforts of Heffernan. wharf.co.uk
John Heffernan Actor 