The Novelist, a $110,000 Gold Coast yearling, is a member of Written By's first crop, the result of a union with Sunlit, while The Playwright is out of Sugarparma.
Trained by Peter Robl, Sugarparma finished fourth in the 2015 BJ McLachlan Stakes under Regan Bayliss, who was aboard for The Playright's narrow-but-impressive debut win over Icarian Dream at Rosehill on November 30 and will again ride on Saturday.
The Playwright is Sugarparma's second foal by Written By, with Tricolours also the owners of the first, Manuscript, an $85,000 Gold Coast yearling who has had just three starts and is already a winner.
"Going up to Magic Millions last year, she wasn't hard to find being a full sister to Manuscript and she was one of the first horses I wanted to see," Moss said.
"She was a little bit different to Manuscript, who was a very strong, physical-looking two-year-old, whereas I thought The Playwright might take a little more time.
"But once we got her home from the sales she really blossomed and every time we did some work with her, or she got broken in, or came into the stables, she just really thrived.
"She's one of those sneaky horses that continues to improve with everything she does and that's what we've seen from her in trials to raceday.
"Her trials were good, but with improvement to come and that's what she did, she improved again, so let's hope she can do that again on Saturday."
The Playwright drew barrier eight in the 1200m BJ McLachlan Stakes, which has attracted a field of 14 plus three emergencies, with Icarian Dream (barrier 13) again a rival, along with high-profile local Hi Barbie (10).