We see Oliver and Laurel before the fatal trip taken by The Queen's Gambit in this Arrow sneak peek. It is from "The Undertaking."
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Arrow is making its way to an explosive season finale. Watch the promo now for "The Undertaking."
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Arrow Season 1 Episode 21 Quotes

Laurel: Then help me understand. If our relationship is going to end, at least let it end with honesty.
Tommy: Okay Laurel. Honestly, you belong with Oliver.

Diggle: What did you want?
Felicity: Is that any way to treat a girl who just walked up six flight of stairs?
Diggle: No, it's not. Welcome.