Oliver has a sweet relationship with Detective McKenna. If she didn't have to leave town, they could have given it a real chance.
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Oliver's life is disrupted when the Huntress returns on Arrow. "The Huntress Returns" is the 17th episode of the show's first season.
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Arrow Season 1 Episode 17 Quotes

Yeah, congratulations Ollie. The club doesn't completely suck.

Thea

So you really believe this garbage your mother's selling about Sarah being alive on Fantasy Island?

Det. Lance