People still have a lot of questions about the 1969 moon landing. Giant Leap brings one more to the table: were Neil Armstrong’s first words to the world scripted by others? In this play, the answer is yes. A writer (Tom Stade) and a comic (Lewis Schaffer), gathered in a bunker, have the responsibility of coming up with a memorable line for the astronaut to say on live television as soon as he steps out of the space capsule.

Time is ticking and they’re pressured by the intimidating Jay Weinberg (Phil Nichol), who is supervising the work, by a bright young secretary and by a rather nervous colonel. The dialogue between characters is so intense, loud and fast-paced that you can’t help but be absorbed by the brainstorming session. At some point, creating the perfect line becomes a goal for the audience too and you start to wonder which of those intriguing characters will come up with the famous 'That's one small step for man, one giant leap for mankind.'

Schaffer stands out with his ironic puns, but it's mostly Nichol’s energising performance that fills the room. With so much going on, it’s easy for the actors to break out of character and let a smile escape, as happened once or twice at this performance. But all in all, it’s an outstanding piece of writing by Mickey Down and Konrad Kay, taking us behind the scenes of an historic moment. Mission accomplished.

Pleasance Courtyard, 556 6550, until 31 Aug, 1.50pm,£7.50–£10 (£6.50–£9).