The Actors' Benevolent Fund gala will benefit performers who are temporarily or permanently unable to work because of an injury, illness or disability.
Comedian Michele A'Court is MCing the 90 minute showcase which will feature performances from music legends Shona Laing and Dave Dobbyn, Lawless, and many other actors and artists.
Lawless said the event was about performers and audiences coming together to support actors in need and it was a cause that she was proud to support.
"It's really nice to participate in something by actors for actors. Entertainment is a very important part of the well-being of society and you need performers to deliver that - whether it's in movies or on the stage, a live performance.
"For many, many actors there's no back up. There's no ACC for them. So this is a chance for people who love art, whether you're in the business or not, to contribute to the well-being of [actors]."
The 49-year-old actress - loved around the world for her leading role in Xena: Warrior Princess - told the Weekend Herald that when an actor stops working because of illness, injury or disability it's for an "awfully good reason", so the money raised at the gala would go to people who really need help.
"You don't want to let the side down and it's just part of your being able to contribute in that way, so when actors are sick they're not kidding around."
During the gala show she will read Australian musician Nick Cave's "very poetic" letter My muse is not a horse.
Cave wrote the letter as a response to his nomination for MTV's Best Male artist award in 1996 after releasing his ninth studio album Murder Ballads.
In it he said though he was "grateful and flattered" to be nominated, he asked the nomination to be withdrawn.
"It's about how being rewarded by awards might cause his muse to flee," Lawless said.
"And I think it's about something that every creative person, and we're all creative, needs to be reminded of - that to treat our creativity as something very precious and not try to put a value on it because the value of it is incalculable."
Fellow star Kiwi actress Jennifer Ward-Lealand, who is performing in and helping organise the gala, said many actors regularly performed for different charities, but were hesitant to admit when they needed help themselves.
"Actors are notoriously proud. It's usually people around them who say 'this person is in strife'."
Funds raised through the gala's ticket sales will be distributed by the New Zealand Actors' Benevolent Fund, a charity which formed in 2013.
The organisation supports New Zealand actors through health issues in a variety of ways - be it by paying their utility bills while they go through a round of chemo, or helping to fund medical treatment.
Tickets to the gala - costing between $30 and $100 - are on sale on Eventfinda.
• The Weekend Herald has 50 double passes to the Actors' Benevolent Fund Afternoon Gala on Sunday to giveaway.
This one-time-only event at the Pop-up Globe at Ellerslie Racecourse starts at 4pmAll proceeds from this event will be donated to the Actors' Benevolent Fund.
To enter, email: firstname.lastname@example.org with your name and 'Herald ABF' in the subject line. The first 50 people to email will get the double passes and your win will be confirmed by return email by 5pm Saturday.