[1] The title was inspired by a quote from William Shakespeare's Twelfth Night: "If this were played upon a stage now, I could condemn it as improbable fiction."

In contrast to Private Fears in Public Places and its 54 mini-scenes, Improbable Fiction used the single set of the living room in Arnold's house throughout the play, and one continuous scene, broken only by the interval.

Ilsa also looks after Arnold's live-in bed-ridden mother, who periodically demands attention by banging a stick on the upstairs floor.

Grace shows her illustrations for her children's story "Doblin the Goblin" (with friend Sid the Squirrel), Jess tells her of her vision for her period romance, Vivi explains how her latest detective novel is darker than the last three, Brevis plays a (somewhat tuneless) song "There's Light at the End of the Tunnel" from his musical adaptation of The Pilgrim's Progress, and Clem reads out an extract from his science fiction story (or, as Clem sees it, "science fact", with names changed to protect identities).

Jess never manages to start writing, whilst Vivi is clearly over-writing, and her description of the detective's smitten sidekick is obviously modelled on her and her search for the right man.

Brevis's long list of successfully performed musicals can be attributed to the fact that he was a teacher at a school, and now that he is retired he is stuck.

And Clem gets angry that no-one can follow his incomprehensible plot, and his persistent mispronunciation of words (such as "invulshable" instead of "invincible") drives Brevis up the wall.

When a nervous Ilsa enters and serves the tea painfully slowly, the rest of the group start making wild speculation about her.

With the second act starting exactly where the first one left off, Arnold suddenly hears Jess narrating the story, somewhat in the style of Jane Austen or the Brontë sisters.

"[7] However, the same second act that earned praise from some critics was criticised by Sam Marlowe, saying "The problem is that this parade of comic cardboard cut-outs is impossible to care about, so it's not long before it falls flat," whilst arguing the earlier scenes worked better.

[8] Charles Spencer, reviewing the show on its tour at Guildford, was harsher, suggesting this play was evidence of Ayckbourn's decline.

"[9] It was suggested [1] that the reviews were generally better for the Scarborough production in the context of its 50th anniversary season, whilst expectations on the tour were for something deeper.

Nonetheless, with three professional productions in the three years after the tour ended,[5] Improbable Fiction has maintained a stage life outside of its original run.