Leadership challenge: Labour's Mafia Wars

Jack Straw kisses the hand of Gordon Brown in public, but many suspect treachery behind the scenes. Charles Clarke heads a group of grizzled wiseguys with a vendetta against the Prime Minister after the ousting of their Godfather, Tony Blair. Cabinet ministers swear 'omertà' but in private they are plotting just how to fix it so that Don Brown sleeps with the fishes. Here, Jane Merrick presents a guide to how Labour's warring mobs might go to the mattresses

The Lancashire Mafia

Capofamiglia: Jack Straw

Sottocapo: George Howarth

Consigliere: Janet Anderson

Capodecina: Lindsay Hoyle

Uomini d'onore: Gordon Prentice, Graham Stringer

The family: Veteran MPs from Lancashire who are tribally loyal to Don Straw. Straw has professed loyalty to the Godfather but Don Brown is being warned not to trust the old warhorse. There is even talk of getting Yvette Cooper to put poison in Straw's birthday cake on a visit to the opera.

The vendetta: They believe their boss deserves his chance to be Godfather. Don Straw is also angry at not being made the Godfather's second-in-command. He is said to have traded physical blows with Ed Balls, Don Brown's consigliere.

The game plan: While Straw continues to pay respect to Don Brown, members of his family are publicly questioning Brown's leadership in an attempt to shake him down. Underboss Howarth leaves a horse's head in the Downing Street bed.

Possible method of execution: With the help of another long-serving boss, Geoff Hoon, Don Straw makes a visit to the Godfather and makes him an offer he can't refuse – step aside or be whacked during a visit to the Westminster greengrocer.

The Blairite Avengers

Capofamiglia: Charles Clarke

Sottocapo: Alan Milburn

Consigliere: Stephen Byers

Capodecina: Hilary Armstrong

Uomini d'onore: Peter Mandelson, John Hutton

The family: Headed by Don Clarke, a lover of Italian food, they are battle-worn loyalists to Tony Blair, who was forced into retirement after an attempted assassination in the mafia war of September 2006 (see Curryhouse Plotters). The members are too old to become Godfather and so are putting all their weight behind Don Miliband in a bid to become more powerful. The family includes the deadliest mafioso, Peter Mandelson – known as Il Principe delle Tenebre (Prince of Darkness), who nearly killed off Don Brown in 1994.

The vendetta: To avenge their Godfather Tony Blair's downfall.

The game plan: "Make a marriage" (do business) – with another family, the Primrose Hill Set. Enlist foot soldiers for a shoot-out – 72 would be needed under Labour's rules of engagement – and issue coded messages to destabilise Don Brown.

Possible method of execution: Assassinate Brown in a bloody coup in September.

The Southern Discomforts

Capofamiglia: John Denham

Sottocapo: Bill Rammell

Consigliere: Stephen Ladyman

Capodecina: Gareth Thomas

Uomini d'onore: Andrew Smith, Claire Ward

The family: Group who prospered when Tony Blair was Godfather. But under Brown the mafia has become less popular and is losing turf to another mafia confederation, the Conservatives. The Southern Discomforts occupy neighbourhoods whose existence is endangered – known as "Labour marginals". Some of them face being wiped out altogether. Don Denham, known as Il Misterioso or Dark Horse, is said to have clashed with the Godfather's consigliere, Ed Balls, in a Whitehall turf war.

The vendetta: Fear of losing their neighbourhoods is turning them against Brown.

The game plan: Become increasingly vocal about the threat to their turf and call for stronger leadership from Brown. Use coded messages such as "reconnecting with Middle Italy".

Possible method of execution: Faced with extinction, a desperate member – perhaps even the boss, John Denham – lashes out against Brown.

The Primrose Hill Set

Capofamiglia: David Miliband

Sottocapo: James Purnell

Consigliere: Andy Burnham

Capodecina: Liam Byrne

Uomini d'onore: Jim Murphy, Pat McFadden

The family: Young modernisers and prosecco-loving protégés of Tony Blair who see themselves as the future of Labour's Cosa Nostra. Miliband, a fan of Italian opera, became the head of the family after getting the nod from Tony Blair – now in retirement as their Capo di Capi Re (King Boss of Bosses). This upset Don Blair's other "sons", James Purnell and Andy Burnham, but they have agreed to come together for the sake of the family.

The vendetta: Unhappy at Don Brown's decision to row back on Blair's reforms, including his axing of a new Las Vegas casino, they've had enough.

The game plan: With the help of the Blairite Avengers (see above), use shock tactics. Don Miliband fires the first shot by calling for a "radical new phase" – translation: "whack Brown". Miliband could be immune from being whacked himself because his brother Ed is a loyal foot soldier to Don Brown – but not for long.

Possible method of execution: Someone else will do the dirty work to let Don Miliband take over.

The Curryhouse Plotters

Capofamiglia: Tom Watson

Sottocapo: Chris Bryant

Consigliere: Kevan Jones

Capodecina: Siô*Simon

Uomini d'onore: Iain Wright, Chris Mole

The family: Brown supporters who were behind the attempted coup of September 2006, which triggered a round of tit-for-tat violence. They are so named because some of their number plotted the coup in a curry house in Wolverhampton – a town west of Sicily. They tried to scare Don Blair into stepping down by sending him a fish curry.

The vendetta: The boss, Don Watson, who led the plot, was nearly whacked by Tony Blair and remains loyal to Don Brown. But some members of the family feel they should have been rewarded with key positions under the new Godfather. Instead they have been given jobs cleaning up after hits or carrying messages to other families.

The game plan: Sensing the assassination of Don Brown is near, those disaffected members of the family plot in secret for a leadership bid by Harriet Harman, the moll of union wiseguy Jack Dromey.

Possible method of execution: Playing no direct part in an assassination, will join if a new war is declared.

The Postman Always Shoots Twice

Capofamiglia: Alan Johnson

Sottocapo: Gerry Sutcliffe

Consigliere: Fraser Kemp

Capodecina: Ivan Lewis

Uomini d'onore: Bob Ainsworth, John Grogan

The family: Close-knit mob under Alan Johnson, who has risen from the lowly rank of 'picciotto' – little man – in Labour's Cosa Nostra to become the boss of his own family. Don Johnson used to deliver the post to the Godfather's Tuscan villa. They are known more for their brawn than their brains, but Don Johnson has a large powerbase. There is speculation that the Primrose Hill Set could enlist Johnson to stand on a "dream ticket", as Don Miliband's deputy, in the younger mafioso's bid to be Godfather.

The vendetta: Don Johnson has ambitions to be leader himself and isn't getting any younger – this could be his last chance to become Capo di Tutti Capi.

The game plan: Quietly amass the support of members of various families and the trade union wiseguys. Don Johnson pretends not to want the top job, to protect himself from being whacked by the Godfather's enforcer, Nick Brown. Send signals to Don Miliband and Jon Cruddas, an associate member, or Giovane d'onore, about party unity.

Possible method of execution: Element of surprise.