Clarke Vincent had experienced great but terrible things. Growing up an orphan had subjected her to being lonely, which in turn made her heart a little cold. While her parents -two mad scientist who played around with gene slicing- thought their experiment was harmless, it turned her into something different. There tempering with her mind had enhanced her senses drastically.
She was only ten when her parents ran from her when suddenly, she could do things no other children could do. Suddenly, she could hear conversations that were happening miles away and see through the dark with ease. Her senses had been dialed up to a hundred and it wasn't something a child that young could handle.
When a man with one eye stumbles upon her, meeting her in a police station where she had been brought after being caught stealing, he makes her a deal. She could either spend a number of years in some awful juvenile detention or train as an agent for him. With a slight dislike for cages and rules, she agrees to his deal and finds herself joining an organisation called S.H.I.E.L.D. That's when she's pushed to her limits in becoming something great, in becoming a weapon.
She becomes a lethal agent that would stop at nothing to finish a mission, but when her mission involves a boy with powers of speed, her morals are flipped upside down and suddenly, she fears she may be on the wrong side of a war.
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Summary credit to tinkertaydust
[Edited]