Executive producer Marc Guggenheim says Tommy and Moira aren't taking a dip in the pit, and "we have an explanation for why that is the case."

[Warning: spoilers ahead for Wednesday's episode of Arrow, "The Fallen."]

Thea (Willa Holland) may have gotten a new lease on life in Wednesday's Arrow, but don't expect the dead characters of the CW drama to be joining her.

Oliver (Stephen Amell) made the agonizing choice to join the League of Assassins in exchange for access to the Lazarus Pit and its restorative powers to save his sister, who was close to death after being attacked. The decision was all the more painful because Felicity (Emily Bett Rickards) finally confessed her love for him — going as far as drugging Oliver in a failed attempt to bring him back to Starling City from Nanda Parbat.

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Executive Producer Marc Guggenheim knows fans will likely clamor for dead characters such as Oliver's best friend Tommy (Colin Donnell) and mother Moira (Susanna Thompson) to be revived with the Lazarus Pit, which in comic book lore can raise the dead. Despite the lengthy roster of deceased characters on the show, Guggenheim says the producers don't have plans to use the Lazarus Pit in that way.

He notably doesn't mention Caity Lotz's Sara as being on the "no Lazarus Pit list." Lotz is slated to appear in the untitled Arrow/Flash spinoff, though her character Sara died earlier this season.

In a chat with The Hollywood Reporter, Guggenheim also weighs in on Oliver's potentially dark future, the complications Thea faces after her dip in the pit, and Roy's (Colton Haynes) goodbye.

Is the Lazarus Pit on the table for other people?

Now that we've got it in our world, and we have a lot of dead characters in our world, we will be addressing how it works and the circumstances and things of that nature. I know that is something our fans are going to be very interested in. I'm sure after the events of episode 20, there will be a lot of, "Get Tommy in the pit. Get Moira in the pit." We don't have any plans to do that, but we have an explanation for why that is the case.

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Thea seems OK, but is it safe to assume there will be complications from her dip in the pit?

Everything in the show has consequences, and that's something we've been consistent about. It's something you will continue to see not just through the end of season three but into season four.

We got a sense of Ra's backstory, with him being torn away from them by the previous Ra's. Where did that come from?

One thing we try to do on the show is give our villains a relatable backstory. Very few of our villains come into the world completely evil. They sort of become evil over time. We were just consistent with that philosophy when it came to Ra's. It would be very convenient if he was born evil and then joined an evil organization.

Ra's used to be a loving family man, but is now a brutal killer. Is Oliver in danger of going over the edge like that?

That's very much the concern. In many ways, 320 is a cliffhanger, because it ends with Oliver joining this organization, with us knowing that this is an evil organization. The League of Assassins is not the name of a nice group. Now that he is a member, who knows what he is going to have to do in the course of his ascension to Ra's. It's a true cliffhanger. You don't know where the show is going to go after, after the events of episode 320.

Is Felicity and Ray's breakup part of Brandon Routh transitioning to the spinoff?

Ray is going to remain a big part of Arrow throughout the remainder of the season. We didn't break up Felicity and Ray because of the spinoff. We really had to do it to make it for Oliver and Felicity to sleep together, because we didn't want Felicity cheating on Ray the first time she hooked up with Oliver. That would not be cool.

After his exit last week, Colton Haynes comes back as Roy one more time this season. What are some of the circumstances of that?

The one loop we haven't tied off is the relationship between Roy and Thea. That storyline in episode 22 is really designed to put a punctuation mark on their love affair.

How much Roy will we see in season four?

It's totally based on Colton's availability and what stories we have. We haven't slotted particular episodes yet. We're just at the early stages of planning out the overall storylines for season four. We haven't gotten down to the point where we'd say it's going to be episodes X,Y, and Z. it will be a situation where we have an idea, and then we'll go to Colton, and then find out what his storyline will be.

Arrow airs on Wednesdays at 8 p.m. on The CW.