Perfect cast
Meanwhile, her teenaged sons are getting into scrapes. And, if all this isn't enough, her cooking is life-threateningly awful. In Butterflies, writer Carla Lane, famous for more boisterous shows like The Liver Birds and Bread, created one of the most subtle, poignant sitcoms ever. Laugh until you cry. Literally.

Casting Wendy Craig as Ria was a masterstroke. Already familiar as the squeaky-clean heroine of Not in Front of the Children and And Mother Makes Three, Craig became Lane's Trojan Horse, smuggling a different breed of comedy into British living rooms. BBC bosses were wary of Lane's scripts at first, but she won them over and the result was great comedy delivered by fine actors. Fans of As Time Goes By will love Geoffrey Palmer's tightly buttoned performance as butterfly-mad Ben. Ria's sons are played by Andrew Hall and a young Nicholas Lyndhurst, who displays the comic timing that would make him famous in Only Fools and Horses. Look out for Hammer horror veteran Michael Ripper as Thomas, Leonard's knowing chauffeur.

Daydream believer
If you thought Ally McBeal broke new ground with its use of surreal effects and dream sequences, think again. Ria's battle to keep her relationship with Leonard platonic means that she resorts to some pretty wacky flights of fancy. Butterflies captures that fantastic spirit and wraps it up in the perfect delivery vehicle: a suburban sitcom. Clever stuff.

Tough love
Lane trod a delicate path in Butterflies, placing downbeat, even dark, passages among scenes of more traditional situation comedy. Teenage pregnancy, suicidal impulses and, of course, adultery, all reared their ugly heads, resulting in a post-9pm transmission slot. But the audience loved it. Butterflies was a consistent ratings winner and four series were made between 1978 and 1983.

American adventure
In 1979, a pilot episode of Butterflies was made for the US network, NBC. Lane went to Los Angeles to work on a script but the project failed to re-create the original show's magic and NBC did not commission a series.

Together again?
In 2000, Lane and the Butterflies cast (except for Ripper who had died earlier that year) got together again to make a one-off special for BBC Children in Need. The 15-minute episode, in which Ria marks her 60th birthday and meets up with Leonard again, went down well with the public but no follow-up series has yet emerged.