This show is an uncomfortable watch in more ways than one. The first scene throws us straight into the deep end, it is here that we first meet Charlie, the title character. He is coming round in a hospital bed, screaming and swearing at an unsuspecting nurse who he believes is a Taliban capturer. Immediately we encounter the anger and confusion that is the undercurrent of the show.

But this emotional turbulence is particularly difficult to swallow because of the nature of the play. The Two Worlds of Charlie F is verbatim theatre as it was intended ‐ it is not only about the real traumatic experiences of servicemen and women, but it is actually performed by them.

This is no ordinary piece of theatre, and it is important to bear in mind throughout the show that it exists because of its original purpose as a means of therapy. We are not watching professional, polished actors, but a set of seriously brave servicemen and women on a vitally cathartic endeavour.

It follows that the script is unequivocally frank. Dialogue may have been tweaked by writer Owen Sheers, but all the words are from the real mouths of the real soldiers involved. So we accustom our ears to military slang, to “pink mist” and other euphemisms which make up the play’s darkly witty diction.

Sometimes the honesty of the language leaves a sour taste in the mouth, one sergeant describes his sensations immediately after an explosion: “I tasted burning flesh,” he simply says. There is no need for ceremony and artifice here, blunt honesty suffices to communicate the absolute horror of war.

Unfortunately there are a few ill conceived distractions along the way. The play is organised as a sequence of testimonies about various stages of the experience of war ‐ a structure that is a little jarring at times but is ultimately a successful means of communicating a mish mash of stories. The main downfall of this structure is that while some excerpts are clever and well executed, some are unnecessary and slightly uncomfortable to watch.

A brief lecture educating us as to the specific impacts of a bomb on the human body is curtly informative and leaves us wincing, in awe of the dignity with which the performers handle their hugely disfiguring injuries. Another sequence, however, addresses the process of the rehabilitation centre in a somewhat lacklustre and oddly cheesy dance routine. The diversity of narrative methods used in the show was impressive, but occasionally it resulted in something similar to pantomime, belying the substance on which the play is founded.

That is not to say that humour was not employed successfully. We laugh at the troops’ chummy jokes almost as much as we shudder at their brutal injuries, a combination which establishes humanity as the play’s prevailing principle.

It is this humanity which ultimately makes The Two Worlds of Charlie F so compelling. The play is strongest when it relies solely on plain, unadorned but deeply honest dialogue, such as a sequence in which the soldiers describe the breakdowns of their respective relationships. Often, the play is not only moving because of the personal stories it follows but because of the universal human struggles it addresses. It is clear why the play was awarded the Amnesty International Freedom of Expression Award 2012. Overall, The Two Worlds of Charlie F is a rewarding and enlightening watch which proves the merits of theatre as therapy.