Allison Allen is best friends with Oliver Queen since they were teenagers. She was on that island with Oliver for five years as well, so their friendship grew even stronger.
When they get off of the island, they go to separate cities- Central City and Starling City.
Allison wants to reconnect with her cousin, Barry Allen, since he's pretty much her only family other than the Queen family.
When she returns to Central City, she becomes a vigilante to cross the names off a list her mother gave her to 'right her wrongs'.
Then in the night that the Particle Accelerator exploded, lightning struck her and Barry, putting them both in comas.
But while Barry only has super speed, she has five more abilities.
That night, the Blue Streak aka the Blue Flash aka the Spark was born.
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