When I first heard that a play had been developed based on Dan Brown's book I was intrigued. The book has a complex plot and the film was a fast-paced thriller - not necessarily the sort of material that might develop naturally to live theatre. Well, for me, sadly, the adaptation simply hasn't worked.
I think that the basic problem I found was that there was too much exposition for the amount of action - too much time taken filling in complex plot details that often seemed to be rushed in their delivery. In the movement and staging I was reminded, several times, of "The Curious Incident of the Dog in the Night Time" but whilst those techniques integrated well into that play, in this case they seemed tacked on to provide a backdrop rather than to expand our understanding. There was a lot of projection, which was mostly effective (though a bit wobbly at times) but at times it seemed at odds with the scenery. Actually, for me there was too much scenery and the bookcase, for example, seemed to be on a yo-yo coming in and going out quite unnecessarily.
Nigel Harman as Robert Langdon does a reasonable job of trying to carry the plot forward but there is an inconsistency across the acting that stopped me being drawn in, this was especially true of Danny John-Jules somewhat cod "batty old professor". The cast worked hard but failed to convey any threat or thrill so that despite the pace of the dialogue the perceived pace of the play was somewhat stodgy.
A lot of the audience seemed to have a good time but personally I was unmoved - your mileage may vary.