It's almost cheating to give actress Jean Smart, introduced in Sunday night's episode of Watchmen as FBI Agent Laurie Blake, all the good lines. Structured around Blake's transmission to Doctor Manhattan (who, remember, is living on Mars), the show's third episode begins and ends with her telling a joke with the refrain "...and the hero goes to hell." It might be foreshadowing, but it could also be a signpost: After all, when God tells the version of Doctor Manhattan in Blake's joke that he's condemned to hell, Manhattan sadly replies: "I'm already there."

It's difficult for any character to be introduced mid-season, after audiences already have their hearts set, but Smart doesn't really even need the generous boosts the script gives her (another: "I eat good guys for breakfast," is spat during a tense mausoleum conversation with Angela). Even when she is silently observing those around her, Smart bestows Watchmen with a renewed, electric complexity, one that further undermines the show's cyclical interrogation of who those good guys really are.

Episode three, "She Was Killed by Space Junk," opens by ratcheting the point of view away from the protagonists we were only just getting to know (the not-so-mysterious wealthy inventor; Sister Night/Angela; the rest of the Tulsa P.D.) to center on an entirely new figure. This choice alone is worth remarking on. For most showrunners, the decision to introduce an unknown character as the protagonist of the third episode would be nothing short of narrative suicide: it's confusing, it's destabilizing, it's not typical of how you tell a story. In this case, the script and tight structure of the episode make everything cohere without totally losing the audience, but I doubt creator Damon Lindelof and the episode's co-writer, Lila Byock, could have pulled it off so slickly without someone as fit for the role as Smart.

It takes someone with virtuosity, too, for Laurie Blake is full of contradictions. When she is introduced, it is with the sweep of a red, cape-like coat, although her intentions are the opposite; she works on the FBI's anti-vigilante task force to put "rich a--holes playing dress-up" behind bars. Only, as paraphernalia in her apartment confirms, Blake is a former vigilante herself. While the episode slowly reveals the details — that she was Doctor Manhattan's lover; that she went by the name Silk Spectre — fans of the comic can jump ahead to recognize Blake as the older version of Laurie Juspeczyk, or Jupiter, who also appears as a character in the show's source material, Alan Moore's Watchmen (curiously, in this adaptation Laurie shares the surname of her biological father, a controversial character in the comic named Eddie "the Comedian" Blake). You don't have to keep up with all of these details just yet; there is clearly more to be excavated here, as is suggested by Laurie's grimace when she is mocked by her boss with the question, "and who doesn't want a secret identity, right Blake?"

We rarely see Agent Blake so disarmed. Despite her display of merciless calm during the staged bank robbery, we even might still underestimate Blake, and at our own peril. There are not many worthy roles for older women in film and television, certainly not ones that require playing someone other than a mother or grandmother to a more-important central character. Particularly in a show about superheroes — cultural paradigms of youth and fitness — 68-year-old Smart seems like the odd actor out. Speaking on the phone to Doctor Manhattan, she sounds feeble and forgetful, messing up her own joke: "And — and then —" she stutters, losing her place. "S--t, I messed it up." Only too late do you realize that she's putting you on; that this is a part of the joke, too.

Blake spends the entirety of episode three violently reshaping our presumptions in this way. While the first two episodes postured Angela and the Tulsa P.D. as the protagonists, we are now shown the police in the withering perspective of Blake (another of her great lines: "You know how you can tell the difference between a masked cop and a vigilante? ... Me neither."). When Red Scare and Pirate Jenny introduce themselves with their code names, Blake sarcastically replies, "wow, cool," and we see them as she does: pathetic and laughable. Even Looking Glass, who had seemed to possess an almost supernatural ability to see through suspects, is leveled by Blake, who mocks his "racism detector," and cuts him short by using his real name. Throughout the episode, Smart plays the role with a smile that conveys no pleasure — it is only the projection of amusement, while her eyes and mind are somewhere else, calculating.

Older women, too, aren't often portrayed as desirous, although as the episode unfolds it becomes increasingly clear that Blake yearns for her departed blue lover. This is shown in surprising ways, when it is revealed what exactly Blake carries in her silver briefcase, tucked alongside an Esquire cover showing a younger version of herself sensually pushed up against Doctor Manhattan, and in the evidently unsatisfactory seduction of Agent Petey. It is also a rare glimpse of her vulnerability; Smart's blinked-back tears when she asks Manhattan "we're not really worth giving a s--t about, are we?" reminds us that she is more than just teeth and claws.

But Blake doesn't need to let her armor down to be riveting, such as in the scenes when she spars with Angela. In the first two episodes, actress Regina King was the unrivaled stand-out of Watchmen; now she has an equal to engage with on screen. Both Angela and Blake spring to life in each other's presence, recognizing the danger in the other, and calling each other's bluffs. When the perspective swings back to Angela for episode four, it is fascinating to see how Blake remains just as complicated and compelling in someone else's eyes.

In total, Smart is credited as being in seven episodes of Watchmen, which means she will be with us in some capacity or another until the season's finale. Watchmen will be all the better for it. Even if the script is unable to sustain the incredible caliber of episode three, Smart doesn't need to rely on great lines. When Agent Blake throws her head back and laughs at the potential of Doctor Manhattan's acknowledgment of her transmission at the end of the episode, those are not words. Yet contained in her laugh is the roll of a snare drum. In her laugh are the curtains.

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