Well, "pow!" might describe the dramatic effect created when Terry Johnson brought Freud into collision with Salvador Dali in Hysteria or when, in Insignificance, he holed up those two 20th century icons, Einstein and Marilyn Monroe, in the same Manhattan hotel room where she kindly demonstrated to its propounder the theory of relativity. "Phut," though, would be a better way of characterising what happens here when Steve Martin steers Einstein and Picasso into a Paris bar - despite the fact that, towards the end, there's an explosion which blasts in a time-travelling Elvis Presley.
The piece is set in 1904 at the brink of the century our youthful geniuses were, in their respective fields, to dominate. The bar regulars have a go at predicting what the next hundred years will bring. Their forecasts are either uncannily prescient and very American ("By the end of the century, smoking in restaurants will be banned") or tastelessly accurate ("The city of Hiroshima will be completely modernised"), or spectacularly wrong, or dumb-blonde ditzy ("A yo-yo will be a wonderful thing to play with and a terrible thing to be").
That gives you an idea of the tone to which this play keeps reverting - a facile jokiness which depends upon the lazy superiority of hindsight. When, for example, Brian Shelley's likeably gentle Einstein arrives at the bar, another character fails to recognise him. "I'm not myself today," he apologises, and musses his combed hair to the trademark mad-scientist look. He's already the icon he was yet to become.
As for the promised battle of wits, it's waged very weakly and in fits and starts because Martin's script has too short an attention span to pursue any topic with persistence.
"For me," declares Ben Walden's Picasso, sneering at science, "the shortest distance between two points is not a straight line."
"Likewise," counters Einstein.
It's a neat, if contrived, turn, but the piece fails to take you all that much further into the scientists' ideas and their imaginative implications. Gag-ridden, it also has worrying patches of straight-faced uplift and movie-speak.
"So you say that you, too, dream the impossible and bring it into effect," marvels Picasso, recognising a creative kinship across the disciplines. Tom Stoppard's Travesties with its conjunction of Joyce, Tzara and Lenin, manages to be a hundred times funnier than this, while also sustaining serious debate about the relationship between art and revolution.
The most enjoyable character in Randall Arney's attractively acted production is the bumptious little self-deluded charlatan, Schmendiman (Andrew Nyman) who is convinced he is going to become one of the century's household names because of the potty "inflexible and very brittle building material" he has invented. Martin has him conceitedly deprecating the two real future giants and coming up, as if inspired, with tired old traditional ideas - saying "cheese" for photographs, putting dunces in pointy hats - that he feels will further seal his bid for immortality.
An amusing lesson in the parochialism of self-regard, the character refreshes a play you don't need to be Einstein to recognise as intellectually thin and disappointing.