The actress, who plays school principal Priya Kapoor, disclosed details of the show's unusual filming methods involving summer scenes being shot in the winter.
"With the way that filming works, because of how far ahead we are, usually in summer we're filming winter scenes, so even though you've got these glorious 40 degree days, we're in heavy jackets, sweating our asses off," she told MSN.
"And then when we're filming summer scenes it's winter, so we're in our skimpy outifts with heatpacks stuck to our skin, underneath our clothes, so that we can be toasty warm.
"Or they put heatpacks in your shoes so your toes don't get frostbite."
Gooneratne added: "And one time you could see the actors' breath, that's how cold it was, so they were having us chew ice in between takes, to lower our mouth temperature!"
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