It says something about Tom Stoppard's sense of humour that he considers Shakespeare's longest play (which often runs for over four hours when performed) perfectly fair game to be ultra-truncated into a short, 15 minute performance.
This play is rarely performed these days as nobody really pays to go and see a performance they know will last just 15 minutes. However, the play forms the core of Stoppard's `Dogg's Hamlet' and also effectively forms the last 15 minutes of the comedy performance, `The Complete Works of William Shakespeare (Abridged)', so you may have seen it in one of those contexts.
This play, then, is to Hamlet what `1066 And All That' is to English history - it gives you not everything, but just everything you can remember: it has all the quotable and famous lines and contains just enough plot that you can understand the whole play. And if you already know Hamlet quite well, then the choice of dialogue and scenes for inclusion and the rapid changes from one to another are quite funny; the joke might fall flat on those seeing Hamlet for the first time, but it's a rare hilarious gem for those in the know.
Read the book, or better yet - track down a performance, or use this script to stage one yourself.