By the time the curtain falls on Nick Fisher’s first stage play, you feel that dog Toby – the nominal title character – has had a lucky escape to those great hunting grounds in the sky. Not that the script isn’t extremely funny; it is, and Fisher has drawn some all-too recognisable characters (recognisable, that is, from other comedies if not from most people's lives).

We’re in the kitchen-diner of a barn conversion, complete with glowing red Aga (at times it all seems like an exercise in product placement). This former marital home is the prize which Miranda’s divorce from Guy has earned, even if a couple of decades of betrayal have led up to it. Toby is literally on his last legs and sympathetic vet Martin is prepared to perform the necessary act of mercy.

Then she summons Guy (after all, they shared the dog) – and you realise that he’s as much a “basket case” (in the colloquial sense) as the canine. The fun is fast and furious as James, Guy’s golfing partner, tries to keep out of trouble while it slowly dawns on Guy that Miranda doesn’t need him any more, not that he seems to have been much help in the first place! It seems to have rubbed off on their (off-stage) children as well.

Wisely, Robin Lefevre’s direction makes sure that the momentum keeps going, and he’s very well served by the cast. Nigel Havers is the infuriating Guy, the sort of middle-aged man who keeps in shape and still wears jeans, to the life. His rapid-fire delivery almost makes you forget that Guy is actually a thoroughly unpleasant as well as selfish sort of chap.

Christine Kavanagh’s Miranda works superbly well in contrast; one applauds her attempt to forge a Guy-free life and wants this to continue (though Fisher’s ending is ambiguous). The other two men are satellites around this sun and moon though Graham Seed is likeable as Martin and David Cardy obviously enjoys James’ crassness. Liz Ascroft’s set is a star in its own right.