Spoofing theatre itself is a reasonably old gag (going back at least to "Pyramus and Thisbe" in "Midsummer Night's Dream", and probably further) - and we've seen two strong examples last year with "Play On!" and "Noises Off". But this is the modern-state-of-the-art version with all stops out. Like "Play On!" the play being (badly) done is a fictitious Murder Mystery, although in this case we're witness to one disastrous performance rather than a combination of rehearsals and runs, and there's not a lot of backstage story to go with what's going on on-stage. Instead we see a run with vast levels of disaster piling on one another as set, props, words they don't understand and their fellow actors conspire to endager life, limb and the show going on.
This is very heavy on the slapstick and lacks any kind of higher mind beyond giving the audience a good time. It also has virtually no reference to popular culture post the mid 80s. But it is immaculately drilled slapstick, as the set becomes more and more a deathtrap. Acting throughout is broad, but appropriately so for the material - if it's difficult to pick highlights in the cast, that's largely because they're such a solid strong ensemble.
I will say the script is a little keen to actually go through with the plot mechanics of the murder mystery which seems somewhat irrelevant to anyone's enjoyment (and, indeed, I kinda wish we got one of the two follow-ups that have come along in the UK since this, "Peter Pan Goes Wrong" or "The Nativity Goes Wrong" instead), but as commercial theatre goes (as compared to the subsidised stuff that hits the Canberra Theatre season), this is thoroughly enjoyable stuff.