Zack is in the hallway, slurping down a Big Gulp and admiring his latest detention sentence. He's surprisingly chipper about it, but that's only because he's been chosen as Kelly's date for her birthday party that weekend. Kelly's party is apparently the social event of the season, as everyone is all a-twitter about lining up dates for it. Jessie tells us that since this is the '90s, it's acceptable for women to go to a party alone. Yes, because unescorted women were unheard of in the '70s and '80s. Slater responds to this statement with one of his usual rant-baiting sexist remarks, then comments on how cute Jessie looks when she's being all pseudo-feminist. Get a room, you two. Oh, but not yet, because Lisa's got her eye on a date for Jessie, in the form of her neighbor, Brett. (Sadly, Lisa is not neighbors with Brett and Jermaine from Flight of the Conchords, which would have made this storyline much more palatable.)
Speaking of dates, Mr. Belding is cruising the halls, trying to sucker any warm body into taking out his niece, Penny, on Friday night. After most of the extras literally run away from him, he hits up Slater. Slater asks what Penny looks like, and Richie responds, "She's a Belding." Yeah, I'm not sure I'd lead with that, especially considering that, thanks to Slater's brief fantasy sequence, we can officially award Dennis Haskins the dubious honor of Least Attractive SBTB Cast Member in Drag. (And considering what we'veseen of Mark-Paul Gosselaar, that's quite a feat.) Anyway, Zack and Slater bow out of the date with Penny, and while Screech is willing, Belding basically tells him, "Only if you're the last man standing." Screech runs off to buy a pager in preparation for that eventuality.
While they're chatting, Zack asks Belding to sign his detention slip, which elicits a crow from Belding about how one more detention will equal suspension. Zack quibbles with the tally, but Belding reminds him of his last infraction, which was trying to sell the school to the Japanese. Since when do foreign investors take meetings with high-school students? Anyway, Zack swears his ninth trip to detention will be his last. He seems pretty confident for a guy who was bragging about how much he gets sent to detention not five minutes before.
Cut to biology class, where Lisa starts to fill Jessie in on Brett, but gets cut short by the bell. Zack strolls in just as Mr. Hudson (who seems to enjoy talking like Daddy Warbucks for some reason) to introduce today's lesson on dominant and recessive genes. Meanwhile, Lisa's writing Jessie a note about Brett, which Zack gets caught passing. Daddy Warbucks puts him on the spot, asking what color eyes the offspring of one brown-eyed and one blue-eyed parent would have, like how is Zack supposed to know this when Daddy Warbucks never mentioned which gene was dominant and which was recessive? He advises Zack to check his notes, so Zack reads from Lisa's note: "A really cute babe with brown eyes who goes to private school." Good thing Lisa included the totally irrelevant fact of Brett's eye color in that note! We'll just assume the private-school gene is also dominant, as Daddy Warbucks lets that pass without comment. He moves on to blood type, and again catches Zack in the act of note-passing, but unfortunately Jessie is not as helpful as Lisa and has neglected to weave in any information about Brett's blood type in her response. Instead, Zack's answer to the result of combining O with AB is "I won't go out with him unless I meet him first," which earns him his 10th trip to detention.
Belding's in his office, scraping the bottom of the nerd barrel in an attempt to come up with a date for Penny when Zack walks in with his detention slip. When Belding realizes what it is, the Hallelujah Chorus echoes through the room (no, really) as he rejoices at the thought of a whole Zack Morris-free week. The jubilation is cut short by his wife, who calls to bemoan the fact that he still hasn't found a date for Penny. Why, exactly, Penny needs to be pimped out so hard by her relatives, we will never know. Anyway, it seems Zack is starting to rub off on Belding, because the next thing you know, Belding's blackmailing Zack into taking Penny out. Zack at least manages to get Belding to cough up $20 for the date. Things seem to be going pretty well for Zack until Kelly saunters up to him in the hall and breaks the news that the Max was booked on Saturday night, so the party's been moved to Friday. Ruh-roh! Also, the Max was booked? With what? Since when is it in such demand for private parties?
The next day, Zack limps in to Belding's office on crutches, his leg in a cast, and his head in some sort of...cast headband? Yeah, I'm not sure that's how they treat head injuries. Belding knows a phony cast when he sees one, and calls Zack out for running the skateboard-accident scam before. He tells Zack to pick up Penny at the mall, and to carry a red rose so he'll know who he is. How You've Got Mail of him. Perhaps Zack should carry a copy of Pride and Prejudice as well. Also, why wouldn't Belding just show Penny Zack's yearbook picture so she'd recognize him?
Meanwhile, in the girls' locker room, Jessie is still unsure about this whole blind-date thing, envisioning that Lisa might set her up with the likes of Freddy Krueger, Jason Voorhees or Donald Trump. While I appreciate the fact that the Donald is being lumped into the same class as horror-movie villains, I'm disappointed that they failed to spring for a Trump wig for Screech in the fantasy sequence. Anyway, Jessie reaffirms that she needs to meet Brett first before she'll go out with him. I fail to see how meeting a guy for lunch is any less of a date than going with him to a party, but whatever. Lisa drops off Jessie at Brett's table at the Max, where the two commence with some of the most inane first-date banter I've ever heard. However, it seems to frost Jessie's cupcakes, because after about 90 seconds, she's inviting him to Kelly's party. He accepts, and the two start undressing each other with their eyes for an uncomfortably long time. Everything's hunky-dory until Brett gets up to leave, and we find out that he's about eye level with Jessie's boobs. Seems like a win-win for ol' Brett, but Jessie's less than thrilled and tells Lisa the date is off. Didn't we already cover Jessie's Height Issues in the Casey Kasem dance party episode? Do we really have to go through this again?
Zack drags Screech into the boys' bathroom to hatch his latest scheme, which is that Screech will pretend to be Zack and go out with Penny instead. Considering how eager Screech was to date Penny a couple days ago, it's kind of surprising that he puts up resistance to this, but he eventually acquiesces. Unfortunately, Zack still has not learned that you should always check the stalls before you do sort of any secretive plotting in the bathroom, and after he and Screech leave, Slater pops up and tells us, "It's incredible what you can hear standing on a toilet." He neglects to tell us why he was standing on the toilet in the first place.
Cut to Zack's bedroom, where he's giving Screech a lesson in Being Zack 101. Apparently, being Zack is a lot like being a Brooks Brothers runway model, as the lesson involves wearing khakis, a blue blazer and Docksiders, and walking while snapping your finger, followed by a dramatic jacket take-off and pose. Screech masters it all until the big open-the-door-and-lean-against-the-door-frame finale, which sends him careening down the stairs. This is probably a good time to wonder why, exactly, this scheme has to involve Zack and Screech dressing in matching outfits.
The next day in the hall, after an intervention by Lisa and Kelly to make Jessie realize what an idiot she's being about Brett (which involves Lisa telling Kelly she can't come to her country club because of the new "rich people only" rule, like isn't that always the rule at country clubs?), Slater sets his own scheme into motion, convincing Screech that Kelly would be heartbroken if he didn't bring Penny to the party.
At the party, Kelly and Zack are twirling around on the dance floor, while Slater's standing by the requisite bowl of red punch, already gloating over what's about to happen. Which is that Screech is going to walk in with Penny Belding who, by the way, is totally cute. Screech has embellished his standard-issue Zack outfit with a blond wig for "that extra bit of Zack-osity." We can only assume that the wildly patterned red tie he also added is for extra "Screech-osity." Anyway, Zack makes a beeline for Screech and tells him to scram.
Meanwhile, Jessie's been glued to her booth all night, refusing to dance with Brett. He's finally had enough, and goes to dance with Lisa. Using her magical matchmaking abilities, Lisa gets them to dance together. Blah, blah, blah, Jessie's tall, Brett's short, Jessie's a jerk, Brett's nice. All you really need to know is that they make up and slow dance awkwardly. Now let's get back to the real story!
Despite being told by Zack in no uncertain terms to get lost, Screech and Penny are still at the party, tango-ing away. Slater cuts in and tells Screech that Zack needs to talk to him. With Screech out of the way, Slater points out Kelly to Penny and tells her Kelly would love it if Penny told her how much fun she was having with Zack. Which she does, even slipping in her plans to take "Zack" back to Belding's house and have her way with him. Hmm, it seems our Penny is a little bit of a tart. Maybe Belding should lead with that the next time he's trying to get high-school boys to go out with her. Kelly rears up to insult Penny, but is apparently unable to come up with any of the various synonyms for "slut" that girls have been hurling at one another since time began, and finally settles on "un-nice girl." Oh, Kel. Still, it's enough to stop the party in its tracks, after which Penny and Screech beat a hasty retreat.
Kelly realizes there's something fishy going on (I can't believe the matching outfits didn't tip her off earlier) and confronts Zack, who tries to lie about it for some reason instead of just coming clean about the Belding blackmail. Finally, Kelly asks him point blank, "Did you tell Belding you'd go out with his niece?" Zack admits that he did, although he omits all of the details about blackmail and making Screech his doppelganger. Kelly's basically like, "That's the sweetest thing anyone's ever done for me." You mean accepting a date with another girl on your birthday? Man, Kelly really needs to raise her standards. Or are we supposed to believe that the same girl who couldn't come up with a better insult than "un-nice girl" worked out all of the stuff Zack left out by herself? That seems about as plausible to me as Screech getting lucky at Belding's house, but according to Penny, that's exactly what's happening right now, so...okay.
Quote of the episode Belding: I've got a real problem, guys. Zack: Just wear a hat, sir.
Grade Clare: B+. Although it was totally unnecessary, the sight of Screech dressed like Zack was pretty humorous. If only it hadn't been for Jessie and her stupid insecurities, this episode would have been a solid A.