Although Blindspot has taken a nosedive in the Nielsen ratings, the show has been a creative success in Season 2. It hasn't made an epic jump in quality that some shows — including broadcast procedural actioneers — make in the sophomore season, but on the whole, it has attempted to tell a more compelling and more diverse range of stories. But even modest experimentation brings the potential for missteps. This week's "Senile Lines" put the spotlight on the season's biggest missteps, to middling results.

Despite seeming like the showdown with Shepherd (Michelle Hurd) and Sandstorm was right at the team's front door, Blindspot managed to stall for another week. Last week's cliffhanger — where members of the Tattoo Task Force were deposed for their alleged involvement in Sandstorm chicanery — suggested real consequences for two season's worth of confusion and destruction. Instead, it simply brought the return of the sniveling ADA Weitz (Aaron Abrams) and gave Nas (Archie Panjabi) her big hero moment.

The "new character joins the team" tactic is about as standard Season 2 stuff as broadcast TV gets, but the events of "Senile Lines" embodied Blindspot's season-long bungling of Nas. Before this episode, Nas' arc could only be summed up as functional. She was briefly antagonistic, until she wasn't. She was then positioned as a productive member of the team with Sandstorm knowledge, until she wasn't really anymore. She was Kurt's bridge love interest, sort of, until she wasn't. She was marked for death, until she wasn't.

Ever since the show decided not to kill the character in the spring premiere, Nas has been more toothless than ever. A shrug-inducing death wouldn't have been the "right" way to do it, but this episode suggested there wasn't a hugely improved idea around the corner. Instead of dying, Nas committed career suicide, suddenly taking the heat in Weitz's Sandstorm investigation after no significant conversation between her, Weller (Sullivan Stapleton), or anyone else on the team. In one early scene she expressed a desire to help use her NSA contacts to help Weller navigate around Weitz, and then there she was, admitting full fault for the botched operations, the sketchy procedures, and the conspiratorial questions.

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In a vacuum, this choice makes some sense. A knowledgeable but jaded agent joins the team, learning to appreciate the skills and charms of a band of misfits somehow dedicated to both stopping crimes based on body art and preventing the world's biggest terrorist coup. That's the story Blindspot believed it was telling; Nas' final moment here featured a glassy-eyed speech about pushing forward, rediscovering the value of teamwork, and so on.

The problem with all that, of course, is that Nas never really felt like a human being with identifiable characteristics. She was never a negative — that's what happens when you cast someone as skilled as Archie Panjabi — but rarely was she a positive either. If you're like me, you watched nearly an entire season waiting for the show to find a real purpose for the character beyond keeping the "female authority figure" slot full for another 22 episodes. That Panjabi chose to do this for a year after The Good Wife ended will be forever baffling.

Sullivan Stapleton, Audrey Esparza, Ashley Johnson, Jaimie Alexander, and Archie Panjabi, <em>Blindspot </em>(Credit: NBC)Sullivan Stapleton, Audrey Esparza, Ashley Johnson, Jaimie Alexander, and Archie Panjabi, Blindspot (Credit: NBC)

Nas' lack of personality is not a new problem for Blindspot. In fact, it's arguably one that the show's creative team recognized after last season, as one of the other big directives of Season 2 has been the extended time with Reade (Rob Brown) and Zapata (Audrey Esparza). Given that the show has actually tried with these two supporting characters, it's hard to evaluate them as equally troublesome as whatever happened with Nas over the last seven months. Yet, as the show continues to tease out Reade's emotional turmoil, the improvements are minimal.

It's a similar problem: thrusting Reade into this fraught history that he essentially buried in his subconscious has occasionally made for solid TV. Rob Brown has regularly performed admirably with what he has been given, presenting a Reade slowly losing grasp of the falsities he crafted in his mind place without getting too manic. But once the abuse story turned into an addiction story, Brown was trapped in the most generic beats imaginable.

Now that the show is committed to examining Reade's road to recovery, there's some small potential for improvement. Brown's muted performance in the hospital opposite a guesting Garret Dillahunt was a fine reminder of what he was doing back in the fall before this became a whole ordeal involving suicide, cover-ups, and uppers. And still it doesn't totally feel like much of this will matter, whether Blindspot gets canceled or not.

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Part of the problem is the show's genre and format. Blindspot won't be the last network mystery procedural to feature a couple of solid characters at the top and then some supporting fodder that intermittently gets attention. But there does appear to be a problem endemic to the show's writing style and tone too; it's so serious, tormented, and matter of fact that supporting players rarely get to display personality, even in brief, expositional moments.

Many weeks, these complaints don't matter. When Blindspot is chugging forward with coherent treatment of its ongoing tattoo- and Sandstorm-related stories, it's both better and easier to forget that a handful of these characters aren't that definable. But when the show turns an episode like this one — in full stall mode, complete with a tattoo case about drug trials on foster kids — these problems are impossible to ignore.

Blindspot airs Wednesday at 8/7c on NBC.