A play is not a book is not a film. This seems obvious, but unfortunately people have got a little sideways when it comes to Sideways. Rex Pickett’s theatre adaptation of his novel has just finished its London run to reviews that were as mixed up as they were mixed.

Take Mark Lawson in The Guardian. Lawson states that the play is ‘an adaptation of…the film’ even though he also refers to it as ‘theatricalising the novel’. It can’t be both. The problem, of course, is that the 2004 film is incredibly well known. Many people will have attended the play just to hear the famous line about Merlot. In the novel, the exchange is thus:

Jack: If they want to drink Merlot, we’re drinking Merlot.

Miles: They’re not going to order Merlot. They’re way too hip for that…And if they do, I’m splitting.

Even though the play is based on the novel, there are times a show’s gotta do what a show’s gotta do. The rendition of the line from the film gets one of the biggest roars of the night. But for the rest of the night the book is paramount.

The set design is clever – perhaps so clever that it is a little distracting? But an enthusiastic and engaging cast keep your mind on their characters – and on the writing. Here’s a play based on a novel about a writer. It can take risks with its script – and we expect it and enjoy it. For this writer it was a thoroughly enjoyable adaptation.

There are times when comparing the three versions of Sideways is like analysing the synoptic gospels. Each contains a number of elements common to the others, but each also wraps its material up in a different way. That makes sense because Sideways is made up of a number of almost self-contained scenes, like Bruce Robinson’s classic Withnail and I, which inspired Rex Pickett. So there is the introduction to wine tasting, the visit to Miles’ mother, the restaurant scene, the slow simmering between Miles and Maya, the chase for the rings and the deliberate car crash. There are a few other scenes in the book, some of which appear in the play but not the film.

These ingredients are mixed in quite different ways. The sunlight and scenery of California are leading cast members in the film but whereas Miles is left behind by his old buddy Jack, he finds his own redemption through (but not in) the grape. The book, written in the first person, sees Miles more detached and cynical and yet in some ways more open than Jack to ridiculous and reckless adventure. By the time we take to the stage, Miles is less obviously a loser, doing lads’-bantz happily with sunny Jack. The sun-soaked scenery is necessarily replaced by a hot tub, but the wine flows just as freely.

The women are also treated differently: in the book the characters of Maya and Terra are seen solely through the perspective of Miles; in the film they become more rounded while in the play you wonder how on earth the men have landed partners who are so out of their league.

Yet when it comes down to it Sideways is about bonds of friendship and trust built on shared experience. The individual episodes are strong enough to make it across into other formats (though I am pleased that the boar hunting chapter doesn’t make it onto the London stage). They can be played with to develop meaning.

The ideal companion to book, play or film is, of course, a fine Pinot. Each time I have supped with Miles and Jack and in whatever format, my wine consumption has spiked a little. During my little Sideways season earlier this month, I found myself also reading Jancis Robinson. Bruce Robinson’s characters, as well as Miles, would applaud a commitment to the finest wines available to humanity.

I hadn’t known that there are sequels to the novel. I get the idea that the first sequel is Rex Pickett’s response to the first novel’s film adaptation and massive success. I’ll be checking it out, but in the meantime if you know only the film, pick up the Sideways novel. Miles and Jack have a great time planned for you.