'Arrow' Bosses Talk Oliver's Secret Son, Brutal Ramifications for Olicity: There Will Be 'Serious Consequences

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Secrets don't stay secret for long in Star City.

Warning: Major spoilers ahead from Wednesday’s Arrow. Proceed with caution!

Oh baby!

The Flash and Arrow crossover came to an epic conclusion with the (temporary) death of Vandal Savage, but that wasn’t the moment that left fans in a tailspin. That honor went to Oliver Queen’s soul-crushing decision to keep his 9-year-old son, William, a secret -- and the aftermath is going to be brutal.

After bumping into his son at Jitters, Oliver agrees to keep his unexpected fatherhood a secret from everyone close to him (save for Barry Allen) -- a condition made by his ex, Samantha (guest star Anna Hopkins), as the only way he can maintain any type of relationship with his child.

“It's obviously a very emotional storyline,” executive producer Greg Berlanti says. “It was nice to pay [it] off, especially watching Stephen [Amell] do a lot of the work that he did in the episode.”

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The repercussions of Oliver’s decision will immediately be felt on Arrow, and it certainly won’t be pretty.

“It’s definitely going to come to a head in the middle of the season,” confirms executive producer Wendy Mericle, keeping mum on details. “[I] can’t tell you exactly how that’s going to happen.”

What we do know is Oliver’s secret will have a major impact on his romance with Felicity (Olicity fans, brace yourselves!), who, up until this point, hasn’t faced any major obstacles.

“The fact that he’s keeping this from her – true to what we’ve done on the show, if there’s a secret somewhere, it’s going to have some serious consequences,” Mericle says.

In the episode’s most soul-crushing scene, Felicity confronts Oliver after he lies about running a paternity test on his son’s DNA, a moment that would be conveniently undone thanks to Barry’s jump back in time. “Stop, I cannot hear another lie,” she tells Oliver, as their world crumbles. “It’s more complicated than that,” Oliver tries to justify, but Felicity – more unnerved that he lied than him fathering a child -- isn’t hearing it: “You are the only person on the planet that considers the truth complicated.”

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“We’re really excited about how that’s going to change things and it’s really going to raise the stakes and throw some wrenches into their relationship,” Mericle says, “which, so far this season, has been pretty smooth sailing. There will be some fallout for both of them.”

Theories swirled over the identity of Oliver’s son ever since it was revealed in last season’s Flash crossover that his ex kept the baby against Moira’s wishes and $1 million bribe. The most popular theory among fans was that the then-unnamed child was Connor Hawke, who in comic lore follows in his father’s footsteps and eventually assumes the Green Arrow mantle. The decision to go a different route was partially so producers could keep the character in their arsenal.

“When we came up with the whole idea of it, part of it was we didn’t want to be tied in necessarily to a character like Connor not being able to be part of the show if we made him so young,” executive producer Andrew Kreisberg says of having Oliver’s son be William. “To give us the leeway to still have Connor Hawke be part of the universe -- that was the biggest reason we made that decision.”

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“It’s one of the things all of us are most proud of -- having the kind of partners that we have -- that we’re able to have one scene in one episode in season two knowing that we were eventually going to get to this point and that it’s all tied to Oliver’s mother,” Kreisberg continues. “Susanna [Thompson] hasn’t been with the show for a while and yet her presence is still felt throughout this story.”

Speaking of Barry’s trip into the past, which erased the fiery deaths of Team Arrow and Team Flash in their first failed attempt versus Vandal Savage, manipulating the space-time continuum and keeping everyone alive will have serious backlash, as Barry warned Oliver at the end of the episode. How it will affect everyone’s futures, however, remains to be seen.

“There’s always a price to be paid -- whether or not that price gets paid immediately or whether that price gets paid later on in ways that you don’t foresee, it always comes back to haunt you,” Kreisberg says. “Whether it’s by magic or it’s by time travel, truly the Big Bad is time itself. Time wants to go in one direction -- when people die, the universe wants them to stay dead. Anything you do to change that is going to have a cost.”

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and Arrow fans, what did you think of the epic conclusion of the two-part crossover? What was your most shocking moment? Tell us your thoughts by using the #ETnow hashtag!

airs Wednesdays at 8 p.m. ET/PT on The CW.