Espenson admitted that the hints already picked up by fans regarding August W. Booth's (Eion Bailey) background could be "an elaborate mislead".
"[There] are definitely clues," she told TV Guide. "But are they clues that we put in there so that you would later go, 'Oh my God, it was Pinocchio' or are those clues we put in there to make you think he's Pinocchio when in fact, we're planning an elaborate mislead?
"It's very hard to say at this moment. I've seen the theory that he's Maleficent (Kristin Bauer), which is fascinating! There's more than one way to [give a] clue."
Espenson added that characters in Once Upon A Time are also beginning to speculate about August.
"You're going to see Rumplestiltskin (Robert Carlyle) have his own theory about who he is, which raises questions of its own," she revealed.
"If he were Rumplestiltskin's son, wouldn't the son recognise him, for example? But wait, memories are gone. It gets very complicated.
"It's a complicated mystery and we're going to go a good way's down the path towards solving it this [next episode]."
Once Upon A Time airs Sundays at 8/7c on ABC. UK viewers can catch earlier episodes on the same day at 9pm on Channel 5.
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