The town's former Presbyterian church will be the venue for the five-hour event as owners Mike and Jo Romanes, of Rotorua, say thank you to a community they say has supported them since they arrived to restore the church six years ago.
The couple have spent tens of thousands restoring the 123-year-old building, dubbed "The Churrch", to create luxury boutique accommodation.
The concert, with performances by local artists and professionals singing well-known theatre and movie songs, will be held in the grounds.
Mrs Romanes yesterday said these held about 1500 people.
The free concert will be in the late afternoon and evening of Saturday, January 17.
The event coincides with the Lawrence Summer Arts Festival.
It was a way of thanking the community who had "gone out of their way to make us feel welcome", Mrs Romanes said.
The couple own both the church and former town post office buildings in Colonsay St and are excited about investing in a community they believe had "real and incredible potential".
"We're excited about the potential here and we just love the heritage and historic nature of the town. There's also nothing quite like the hospitality of people in the deep south," Mrs Romanes said.
The show begins at 6pm with performances by several local artists and a Christchurch-based magician.
The Off Broadway group, which features songs from Il Divo, Broadway shows and even The Rat Pack, will take the stage about 7pm.
The show will end about 11pm.
If wet, the concert will be transferred to the Simpson Park complex in Lawrence.
