All's well that ends well: The man who was Shakespeare's inspiration

This is the story of a picture of John Fletcher, which will be the subject of a public appeal launched this week. Without him, we might not have had 'The Tempest'. Arifa Akbar tells the tale of the upstart who snapped Shakespeare out of a mid-life crisis

It was 1610 when William Shakespeare's mid-life crisis hit. The Bard, then 46, knew his glittering career as Britain's foremost playwright and poet was on a downward spiral. The man who had once drawn the most fashionable of crowds to his sell-out productions at the Globe was panicked: he feared his heyday as a leading dramatist and head of the King's Men Theatre Company, was well and truly over.

His plays had lost their lightness of touch, become dark and left him not nearly as popular as he had once been. Disenchanted, Shakespeare pondered a retreat from his Bankside theatre base, a swift exit stage left back to his hometown of Stratford-upon-Avon for a quiet retirement.

But then Shakespeare met John Fletcher, a bold writer, 15 years his junior and a long-time admirer of the elder playwright. Fletcher was one of the most prolific and influential playwrights of his day, one of eight dramatists under regular contract to the company, along with Shakespeare and Philip Massinger, Thomas Heywood, Thomas Dekker, James Shirley, William Rowley and Richard Brome.

But it would be Fletcher who would become one of the biggest influences in Shakespeare's later life, a man who would bring new dimension of tragicomedy to the great bard's writing and reinvigorate his career.

The National Portrait Gallery will launch a public appeal this week to save a picture of the Jacobean playwright, believed to be the only surviving portrait painted in his lifetime. The gallery hopes to raise £218,000 to buy the painting, which will serve as a permanent reminder of a forgotten man who became Shakespeare's friend, co-writer and creative inspiration.

Academics say Fletcher's influence on the Bard should not be underestimated. Many believe that after he met Fletcher, Shakespeare was spurred on to write several important works, including The Tempest, A Winter's Tale and Cymbeline – lighter plays which might never have been written had it not been for Fletcher's refreshing influence.

Yet after his death in 1625, Fletcher became the "forgotten collaborator"; his talents overshadowed by the colossal genius of Shakespeare.

"It is not just that Fletcher was a really important colleague and collaborator of Shakespeare, but it would almost complete our group of significant writers who created the modern English language," said Sandy Nairne, director of the NPG.

If purchased, the gallery says, the portrait, currently owned by the 7th Earl of Clarendon, would become part of a five-year research project examining the gallery's pictures from the period and would be a wonderful addition to its collection of Elizabethan and Jacobean writers.

Theatre aficionados say Fletcher should not be remembered just as a collaborator but as a talented dramatist in his own right whose fame once rivalled Shakespeare's. Writing about the most influential men of the time, John Dryden, the 17th-century poet and literary critic, hailed Shakespeare, Ben Jonson and Fletcher as a "triumvirate" and did not distinguish between their talents.

Gregory Doran, the chief associate director at the Royal Shakespeare Company in Stratford-upon-Avon, who has directed three Fletcher plays and hopes to stage what he believes is Cardenio, a lost Shakespeare and Fletcher collaboration, says the portrait reflected Fletcher's immense profile and sway.

It was Fletcher's The Tamer Tamed, his 1611 sequel to The Taming of the Shrew, that provided a restorative for Shakespeare. "Nearly two decades after The Taming of the Shrew was written, Fletcher wrote an answer to it, turning Shakespeare's play on its head," Mr Doran said. "It was something of an antidote to Shakespeare's play in which the main character, Petruchio, gets tamed by his wife, so reversing Shakespeare's play in which Katherine gets tamed.

"He included some fantastic songs in which all the women come along in support of the second wife who has decided to teach Petruchio a lesson. One song is called 'Women Must Wear the Trousers'.

"Shakespeare realised he was getting a bit out of fashion at the theatre and that some of the young whipper-snapper dramatists might have something interesting. He had heard there was a sequel to his play being staged and went to see it. He thought it wasn't bad and this put Fletcher on the map," Mr Doran said. "Fletcher rejuvenated Shakespeare's career. He knew Shakespeare should keep writing."

Literary collaborations were common, with teams often working on one aspect of a play – the plot or romantic and comic content – a process echoed by Hollywood studios in the 1930s.

Fletcher and Shakespeare set about working on a number of ideas. The partnership resulted in three joint productions, King Henry VIII, The Two Noble Kinsmen and Cardenio, a tragicomedy based on an episode in Miguel de Cervantes' Don Quixote.

Cardenio, when rediscovered, was at first regarded as an 18th-century text. "It was discounted as being a Shakespeare play because academics thought it read too much like Fletcher, and they did not know that the two men collaborated to such a degree at the time, as we know now," Mr Doran said. A substantial part of the play has now been found and he intends to develop a production of it with a Spanish theatre.

Soon after writing King Henry VIII, Shakespeare bought a London property, suggesting that, once again, he regarded the capital as his home. "What Fletcher did was to lighten up Shakespeare's work. Shakespeare went from writing King Lear and Macbeth to writing The Tempest, A Winter's Tale and Cymbeline, plays that changed from tragedy into ones that offered a sense of redemption and hope. I believe this was a result of Fletcher's influence. If they had not met, we may not have these works," Mr Doran said.

But it may have been precisely because Fletcher was such a fine collaborator, having also worked extensively with the playwright Francis Beaumont, that his own genius has been overlooked until now, Mr Doran said.

"He loved collaborating and he was great at it. But it is because Fletcher collaborated with Shakespeare that his reputation was tarnished rather than enhanced; all it served to do was remind us he was not Shakespeare, when set alongside his titanic talents.

"But when you study the plays he wrote by himself, you realise he was a terrific writer. The reason his plays have not been revived sooner is the risk factor – few people have done him in the past – but they are really worth doing and we want to do a whole series at the RSC," he said. But just as Fletcher's creative input is credited for reviving Shakespeare's fortunes, the collaboration also saw the Bard's writing career in London come to a crashing end. During an early performance of King Henry VIII in 1613, the cannons in Act III set fire to the thatched roof of the Globe and burned it to the ground. Shakespeare was so dejected that he headed back to Stratford-upon-Avon for good.

What Fletcher offered Shakespeare in the few years that the men worked together cannot be overestimated. Many scholars believe him to have been the modern inventor of tragicomedy. "Fletcher made tragicomedy a fashionable form and Shakespeare thought 'this is what audiences want so I'll follow the trend,'" Mr Doran said.

Patrick Spottiswoode, the education director at the Globe Theatre, which staged Fletcher's The Maid's Tragedy during the theatre's re-opening season in 1997, said it was at this time that Fletcher became a major 17th century figure, celebrated for his "luxuriant fancy and flowing wit" and collaborating with Nathan Field, Ben Jonson's favourite boy-actor.

Fletcher's personal life was every bit as colourful as Shakespeare's. Known as a jolly, generous-spirited character on London's theatre circuit, he was thought by some to be the lover of Beaumont. John Aubrey, an incorrigible gossip and writer, observed that the pair "lived on the bankside, not far from the playhouse, both bachelors who lay together and had the same clothes and cloak between them." While others dismiss this as scurrilous rumour, it nonetheless added to the bohemian mythology surrounding Fletcher.

His big solo dramas include The Island Princess, set in the spice islands of the Far East and tackling the theme of colonial enterprise, and The Woman Hater, which places women characters at the fore.

While those who could were fleeing London for fear of the plague in 1625, Fletcher stayed behind to have his tailor make some new clothes. Aged 46, he fell sick and died. His importance was reflected in his burial site – in Southwark Cathedral, where he shared a stained glass window with Shakespeare, Spenser and Chaucer. But after a bomb in Borough market shattered the cathedral's windows in 1940, the replacement excluded Fletcher, "a physical manifestation" said Mr Doran, "of how he got written out of Shakespeare's life".