The series, Thatcher - the Downing Street Years, could undermine any attempt to heal the Maastricht rift at the party's annual conference in the same month.
'It's no holds barred,' Hugh Scully, executive producer of the series, said. 'People will be astonished. She talks freely and openly about her colleagues and everything else.'
Clips from the programmes, shown at yesterday's launch of the BBC 1 autumn schedule, show Lady Thatcher talking about some of the party 'grandees' who had resisted her appointment as leader.
'They had that biblical weakness,' she says. 'Vanity, vanity, all is vanity. They thought that a grocer's daughter didn't know how things ought to be done . . If they didn't help our cause, they had to go.'
Lord Prior, a member of her first Cabinet derided as a 'wet', describes her attitude as 'dictatorial' and 'totally unreasonable'.
Others including John Major are equally frank about her. The one senior minister to refuse to take part was Michael Heseltine, President of the Board of Trade, who resigned from her Cabinet over the Westland affair and then, by running against her for the leadership, started the events that led to her downfall.
Lady Thatcher was paid what Mr Scully called 'a substantial sum' for taking part. The programmes - to include interviews with Ronald Reagan and Mikhail Gorbachev - will be screened on Wednesday evenings after the Nine o'clock News and coincide with the launch of her memoirs.
Mr Major will find little else to comfort him. An edition of Panorama will be entitled 'John Major - can the Prime Minister survive?' and there is to be a rerun of the much- praised 1990 drama series House of Cards, about the Conservative Party. This will be a curtain-raiser to a four-part sequel, To Play The King, that begins in November.
The rest of the schedule represents the first attempt by Alan Yentob, controller of BBC 1 since January, to get to grips with its ratings problem.
The popular BBC 2 comedy, Absolutely Fabulous, switches to BBC 1, where it should attract a large audience, and there will be yet another series of Last of the Summer Wine, now in its 21st year.
Noel Edmonds appears in Noel's House Party, Telly Addicts and Noel's Garden Party, a selection of clips from his live appearances. Danny Baker, a Radio 5 presenter, hosts Danny Baker After All, a talk show, and a new audience participation show, Happy Families, makes its debut in September.