[Warning: Some spoilers ahead.]

A powerful member of the al Ghul family is heading to Starling City, and they're not going down without a fight on Arrow.

Nyssa al Ghul (Spartacus' Katrina Law), daughter of the dangerous (and often name-dropped) Ra's al Ghul, comes into Oliver Queen's (Stephen Amell) orbit in this week's episode of the CW comic-book series, "Heir to the Demon," in an attempt to take back what's rightfully the property of the deadly League of Assassins: Sara Lance (Caity Lotz). The episode heavily features the Lance family in flashbacks.

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"Second to [Ra's al Ghul], [Nyssa]'s one of the most important figures in the League. They sent their first round of minions to come for Sara and that didn't go so well for them, so now they're bringing out the big guns," executive producer Andrew Kreisberg told reporters.

Nyssa's introduction will have a significant effect on everyone in Starling City -- but not in the way that they may have imagined. "The way Nyssa comes into the story is in a far more provocative and surprising way than the last round," Kreisberg hinted.

By bringing in a character such as Nyssa, who hasn't been featured as prominently in popular media, the Arrow producers had room to play with her characterization. (She has been highlighted in only a handful of DC Comics titles.) For one thing, this iteration of Nyssa has a slight hint of a British accent and a deep connection to Sara. "Everything about her is wide open," Law said of her stunt-heavy role.

Law did feel the pressure portraying a character who was supposed to have gone through combat training for a good portion of her life. "She is precision and precise and everything she does has a purpose and an intent, so I tried to make sure my movements were sharp -- that was the biggest stress," the actress admitted.

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Though Arrow, as of late, has focused on the Lance family dynamic -- and certainly Wednesday's episode continues that trajectory -- Kreisberg said that the next batch of episodes, kicking off Feb. 26 after a short break, are villain-centric ("villains a go-go," as he endearingly termed it). "It's just villain, villain, villain, great big villains, one after the other," Kreisberg said, hinting that some will be "returning favorites and a couple of amazing brand-new ones."

Executive producer Marc Guggenheim added that episodes 14 through 18 "are very much the villains' chapter [of the story] and it builds" to episode 18, which he promised is Arrow's "big mid-midseason cliffhanger, if you will."

The Hollywood Reporter highlights four other notable season-two teases from Guggenheim and Kreisberg.

Birds of Prey arc will "get there": The 17th episode, airing March 26, won't be a direct adaptation of the Birds of Prey comics; instead, it'll have an Arrow spin. "We gave ourselves room to grow and evolve," Guggenheim said. "Birds of Prey is very much the same thing. You're not going to end up with the Holy Trinity of Oracle, Black Canary and Huntress right out of the gate. We'll get there." When the Huntress (Jessica De Gouw) returns, "Helena is gone, all that's left is the Huntress," Kreisberg teased. "She's become consumed by this vengeance for her father and when we see her she's in a very haggard and worn-out state. It's the big final confrontation between her and her father, and Laurel (Katie Cassidy) gets in the crossfire, and the Canary has to go into the rescue."

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Roy isn't in the clear yet: Though the last episode finally saw Roy Harper (Colton Haynes) join Team Arrow, with Oliver introducing him to Felicity (Emily Bett Rickards) and Diggle (David Ramsey) as part of his team, Roy will still be struggling with his powers the next time viewers catch up with him. "The next five episodes really chart Oliver's attempts to keep Roy on the straight and narrow," Kreisberg said. Roy's interactions with the other members of Team Arrow will be unfurled in future episodes. "The cave's getting full," Kreisberg said with a laugh, "and we don't shy away from the fact and we're hopefully using that to our advantage."

Isabel's return trip: What has Isabel Rochev (Summer Glau) been up to since viewers last saw her? The businesswoman, who has been on the periphery as of late, will make a return appearance in the 18th episode of the season. "We'll find out what she's been up to," Guggenheim teased.

Details on the Suicide Squad episode: The teases have been sprinkled throughout the series, with the Suicide Squad set up in last week's episode. Producers revealed that the 16th episode, airing March 19, will be titled "Suicide Squad." And yes, it will revolve around the Suicide Squad. The episode will see Lyla (Audrey Marie Anderson) return, with her recruiting Diggle for a mission, and she "saddles him with the Suicide Squad, including Floyd Lawton (Michael Rowe)," Kreisberg revealed. There will be Diggle-centric flashbacks during his time in Afghanistan with then-friend Ted Gaynor (Ben Browder).

Watch a preview of Wednesday's episode below.

Check back Wednesday evening for a postmortem on what's to come.

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

Email: Philiana.Ng@THR.com

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