Former Stormont Minister Jonathan Bell made a number of shocking revelations during his first day of evidence at the RHI inquiry on Thursday.
Mr Bell who was Enterprise Minister at the time the RHI scheme was closed, painted a picture of a party ruled by special advisers and of how he was the "victim of a massive smear campaign".
Mr Bell told the inquiry a submission on RHI had been kept from him for months and cost control measures designed to rein in the scheme's over expenditure had to be delayed for four weeks.
He rejected claims from his Spad Timothy Cairns that the submission was discussed with him on a number of occasions and said Mr Cairns "made up" a number of claims in his written evidence to the inquiry.
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Mr Bell said that he was told by Mr Cairns that DUP Spad Timothy Johnston did not want the RHI issue "progressed" as he and his brother-in-law had interests in the poultry industry.
It was put to Mr Bell that Mr Cairns claimed in his evidence that Mr Bell was compiling information on DUP members private lives.
Mr Bell rejected this suggestion totally.
"It was Timothy Cairns who explained inappropriately in garish and lurid detail, the sexual misbehaviour of two DUP ministers," Mr Bell said.
He also told the inquiry how Mr Cairns told him about an encounter between Head of the Civil Service David Stirling and DUP Spad Dr Andrew Crawford.
Mr Stirling allegedly told Dr Crawford "'you kept this scheme open for the benefit of your family and you've done significant budgetary damage to Northern Ireland."
He also rejected as totally untrue a claim he attempted to break the finger of special adviser Timothy Cairns - which was made in his evidence to the inquiry.
That allegation is "untrue, completely without foundation and has no basis whatsoever in fact", said the former DETI minister.
"I have never tried to break anybody's finger and never would."
Claims that he threw a punch are also false, he says - that's something "I have never ever done."
He also claimed the then head of communications in the Executive Office David Gordon was briefing against him as a "monster who had to be put to sleep".
He also alleged that broadcaster David Blevins was briefing the DUP to discredit him using his Christian faith, a claim rejected by Mr Blevins' employer Sky News.
The DUP said it had no comment to make while the inquiry continued.
Mr Bell will be back before the RHI inquiry on Friday morning.
Here's how the day unfolded: