Alright, so imagine you're in a game of tag with your friends. One of the players tags you, but you say "wait, I wasn't ready yet!" and ask the other players if they saw what happened. They all say they did, and they agree that you weren't ready when you got tagged.
That's kind of like what happens when someone makes a plea in equity. Equity is a fancy word for fairness, and it's a type of law that says the court should do what's fair in each individual case, rather than just following set rules.
So if someone makes a plea in equity, they're asking the court to do something that might not be in the rules, but it would be fair in their particular case. It's like saying "wait, I know the rules say this, but in my situation it would be fair if you did something else instead."
For example, let's say you borrowed some money from a friend and promised to pay it back in a month. But when the month came around, you lost your job and had no way to pay it back. If your friend took you to court for the money, you could make a plea in equity and say "I know I owe the money, but it wouldn't be fair to make me pay it back right now when I'm out of work. Can we come up with a different plan, like me making small payments over a longer period of time?"
So that's what a plea in equity is all about - asking the court to do what's fair in each individual case, even if it's not exactly what the rules say should happen.