THR debuts a first look at Wednesday's episode featuring the two conspirators.

Slade Wilson's vengeful plan to wreak havoc on Oliver Queen has hit a rough patch on Arrow.

Slade (Manu Bennett) brings his underling, Sebastian Blood (Kevin Alejandro), into his office after Laurel (Katie Cassidy) nearly unravels the plot when she discovers through Sebastian's institutionalized mother that he killed his own father. In a clip from Wednesday's episode "Blind Spot," which The Hollywood Reporter exclusively debuts, Slade interrogates Sebastian on why he's suddenly lost the skill of covering his tracks.

"You know how close you came to allowing the vigilante to destroy everything?" Slade asks.

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"Someone spoke out of turn. I've taken care of the problem," Sebastian replies, almost systematically, a hint that his mother may have dealt with the repercussions of her untimely reveal to Laurel.

But Slade isn't satisfied with Sebastian's response. "Laurel Lance is the problem," he says, calling Sebastian's recent moves "sloppy" -- before issuing a threat. Is the Slade-Sebastian alliance crumbling?

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

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