User Not Found, The CoffeeWorks Project review - solo play set in a café offers food for thought

Who is that slithering on the floor by your foot, or coming to rest by or upon your knee?

Audiences lucky enough to find themselves at User Not Found, the latest from the ever-enterprising site-specific company Dante or Die, should be prepared to swivel this way and that as they take in the hairpin changes of tone achieved across 90 minutes by the play's invaluable solo performer, Terry O'Donovan, whom we find in mourning-induced freefall.

Chris Goode's play casts Dante or Die co-founder O'Donovan as a character called – you guessed it – Terry, first glimpsed seated amongst the 50 or so patrons at the Nine Elms café (great cookies!) in the shadow of Battersea Power Station where the play is currently being performed. (Premiered last summer at Edinburgh, the current tour will conclude with a mid-June visit to the Irish city of Cork.) Confronted first with the unanticipated departure of his lover of nine years, Luka, who subsequently dies, Terry narrates this double whammy via headphones that allow the story to burrow deep inside the listener.Weaving his way around the room as if embarked upon a prolonged exorcism, Terry chronicles not just loss but a digital landscape that tends sometimes cruelly to hang on to the living: each audience member gets a smartphone to go with the individual headphone, as if to remind us that one's social media imprint can endure long after the individual has gone. (Just think how often Facebook acts as an impromptu online in memoriam.) As a performer, O'Donovan's ready smile and warmth prove aptly seductive, whether he is proffering chai latte and a lemon poppyseed muffin as a defence against mortality or doing battle with the presence of Norah Jones in his dreams – or is it Sheryl Crow?  

A self-described "Anybody", the Terry before us individualises the common experience of a grief that, in his case, happens twofold. The first body blow is that delivered by the end of his relationship with "bare-faced Luka who I loved and who left me": a personal rejection that lives on via objects (an old pair of glasses) and memories that won't be shoved aside. But Terry soon discovers that his very specific, embittered loss widens out to embrace the grief generated when someone dear to us dies: "And now at last everyone knows how I felt because now [Luka] has left them, too." (Others besides Luka soon come to feel every bit as real, not least Luka's mum, Maria, who receives the mother-of-all voicemail messages, and a café denizen, Giancarlo, rather enticingly referenced as "a pansexual flirt".) 

The material could easily descend into an unwieldy wallow but both O'Donovan's performance, and the director Daphna Attias's corresponding gift for shifting gears, make room for a range of responses as varied as the sounds on our phones – artificial birds one minute, a waterfall the next; the unforced lyricism of the writing (rain gets compared to "applause from a small sad audience") helps as well. What does it mean to be someone's Online Legacy Executor, as Terry gets appointed here? User Not Found is grimly funny about both the curse and the blessing of memory, which is to clock Terry's urge to obliterate Luka on the one hand, and to preserve him just the same.

It seems appropriate that Dante or Die's previous show, Handle With Care, was set in a storage unit insofar as phones function as handheld equivalents of precisely that. This latest piece ends with a hugely touching invitation to us to connect even as the Terry who has all but encircled us, Puck-style, slips away. Where did he go, the audience can be heard asking, and will he come back? Hard to say beyond giving thanks for the memories: it's been a terrific night.

• User Not Found at The CoffeeWorks Project, Battersea Power Station, to 2 June, then at Ireland's Cork Midsummer Festival 16-17 June. 
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