The Haystack
Hampstead Theatre, London

AL BLYTH’S debut play may have hit the stage over six years on from the release of Edward Snowden’s National Security Agency leaks that inspired it but it still manages to shock.

In it, Neil (Oliver Johnstone) and Zef (Enyi Okoronkwo) are two graduate whizz-kids whose technological prowess sees them rapidly progressing up the ladder at GCHQ’s Cheltenham spy base by impressing their officious boss Hannah (Sarah Woodward).

Dressed in hoodies and tracksuit bottoms, they find themselves “getting the keys to the Ferrari” as they are recruited onto a counter-terror case. They casually intrude upon conversations, trace medical records and relationship histories with chilling ease while munching Maltesers.

Meanwhile, young Guardian journalist Cora Preece (Rona Morison) has been making waves of her own by landing damaging scoops on arms deals between the Ministry of Defence and the Saudi monarchy via an asylum-seeking Saudi princess.

But when her source is silenced she loses her job and topples rapidly into a whirlwind of depression. The two worlds collide, in somewhat predictable fashion, when the voyeuristic Neil abandons all propriety in a mission to save her.

A sluggish back end of the opening half is offset by a concise, gripping second act in which the wicked web of surveillance begins to ensnare all involved.

A dextrous Johnstone and a convincing Morison both pull off impressive performances in challenging roles, while the rest of the cast tick all the required boxes.

Sadly, a clunky set with a few too many screens and bafflingly unfocused projections continuously distracts from the action. Putting the digital realm onto the stage is never easy and Tom Piper’s set doesn’t really pull it off.

Nevertheless, Blyth’s elaborate script is jam-packed with interesting insights and clever touches. One of many is how surveillance can be, and often is, harnessed by malicious allies, as was also shown in the excellent Official Secrets film last year.

As with Snowden’s leaks, The Haystack is another critical warning of the huge threats to life an untamed surveillance state poses.

The question is, who's listening?

Runs until March 7, box office: hampsteadtheatre.com