A man who escaped a Brisbane nightclub during a firebombing attack but returned to rescue others went home and cried in the shower, an inquest has heard.
An emotional Clarence Bingham told the inquest into the 1973 Whiskey Au Go Go attack on Thursday he found his way out after smoke started to fill the building but went back in.
Mr Bingham - who said he wasn't there as a nightclubber, but instead to pick up tickets in his capacity as a printer - arrived at the club about 1.50am on March 8.
He sat at a table and spoke to club manager and long-time friend John Bell before noticing black smoke coming up the stairs.
It was only about 10 minutes after Mr Bingham's arrival that two drums of fuel were thrown into the downstairs foyer of the nightclub in Brisbane's Fortitude Valley and set alight.
Mr Bingham tried to follow Mr Bell in the thick smoke to get outside, but the lights went out almost immediately, plunging them into darkness.
He followed voices, finding the fire escape that led into an alleyway downstairs.
Mr Bingham told Mr Bell he was going back inside and first spoke to people coming through the smoke out the fire escape, helping them to safety.
He then got up about six steps, but the smoke was too thick and he had to come out.
They tried again to get inside, but the fire escape door had closed.
Mr Bingham and Mr Bell hit it with a hammer, but it was only after the fire brigade arrived the door was bashed down.
At the top of the stairs Mr Bingham saw an older man sitting gasping for breath, but firefighters said they had to get inside.
"So I don't know what happened to that fellow," Mr Bingham said, his voice cracking with emotion.
"I never saw him again so maybe someone else took him out."
Mr Bingham told coroner Terry Ryan he couldn't recall how many people he helped get outside.
Asked whether he had any long-term health issues, Mr Bingham replied: "I had a cry in the shower that night when I got home and that was it. I still get a bit emotional though."
He had to throw away the clothes he was wearing because "it was as if they had been dipped in oil," he said.
More than 60 patrons and staff tried frantically to escape as air conditioning vents acted as chimneys, pouring black smoke into the club.
Survivors smashed windows to scramble to neighbouring roofs, but 15 people succumbed to deadly smoke, with autopsies confirming their death from carbon monoxide poisoning.
Two men - John Andrew Stuart and James Richard Finch - were convicted in 1973 of murder over the attack in 1973 and sentenced to life in prison.
Both men have since died.
The new inquest was ordered after the firebombing was mentioned in a trial in which Vincent O'Dempsey and Garry Dubois were convicted over the deaths of Barbara McCulkin and her daughters.
That trial was told the killings may have been motivated over fears Ms McCulkin would try to implicate O'Dempsey in the firebombing.
O'Dempsey - who sat in the court during some testimony - is expected to testify during the last week of the sitting.
Dubois was scheduled to give evidence, but was found dead in his cell at Maryborough Correctional Centre last year.
The inquest continues.