Paul McCartney and Jane Asher attend a performance of “Twang!!”

From Wikipedia:

Twang!! is a musical with music and lyrics written by Lionel Bart and a book by Bart and Harvey Orkin, an American theatrical agent and former writer for The Phil Silvers Show. When production faced issues, American writer Burt Shevelove was called on to help fix the book. The piece, a spoof of the character and legend of Robin Hood, was a disastrous box-office failure and cost Bart his personal fortune.

After a preview in Manchester, Twang!! opened at the Shaftesbury Theatre in London’s West End on 20 December 1965 and closed on 29 January 1966 after just 43 performances, receiving scathing reviews and playing to mostly empty houses. Bart produced it with Bernard Delfont and John Bryan, and Joan Littlewood directed but quit before it opened. She was replaced by Shevelove and Bart. Twang!! is remembered as “the most expensive flop” in West End history up to that time.

In 2008, the Estate of Lionel Bart commissioned Julian Woolford to write a new book for the musical which was performed in 2013 at Guildford School of Acting. This version is now licensed through MTI.

Synopsis

Robin Hood and his Merry Men attempt to break into Nottingham Castle, in a variety of preposterous disguises, in order to prevent a marriage between the nymphomaniac “court tart” Delphina and the hairy Scots laird Roger the Ugly, arranged for the purpose of securing the loan of Scottish troops for bad Prince John.

The new version is a “meta-musical” with a completely different plot. Robin Hood has lost his ‘Twang’ and is not the hero he once was. Much the Miller’s Son arrives in Sherwood Forest having run away from home and is arrested by the sheriff. He is rescued by Robin and the Men before discovering that in Nottinghamshire life is a musical comedy. He falls in love with Delphina whilst Maid Marion helps Robin find his missing ‘twang’ before King Richard returns to re-establish order. […]