The episode starts off in Mr. Tuttles class where students pair up and decide to create their own inventions. Such ideas arise as a fold-out surfboard made from cardboard. Others include super powewred rollerblades, and last but not least, Zack and Jessies hidden microphone shaped in the size of a pen. As usual this little device will cause dire conquences later on in the episode.
The biggest development of the episode however was the arrival of Slaters old girlfriend from Germany, Jennifer, as she has now transferred to Bayside. Slaters in a bind though as he is going out with Jessie. The gang tries to beat around the bush with telling her about the Jessie/Slater relaionship but as usual the pole smoker Screech opens his mouth which leads to Jennifer walking out of The Max in a heated mood. Later that day Zack and Jessie give Screech the pen to walk around the halls and see if it works. Sure enough it catches Slater and Jennifer talking to each other and even having Slater slip her his number. Jessie becomes outraged and puts Slater into a headlock while spray-painting "Death to Slater" on his locker. Slater tries to play it off that he was seeing her to call it off but even Einstein wouldve figured out that he was lying. Jessie swallows her pride and gives in and tells Slater that she'll give him one more date with Jennifer to see how he feels about her and then he can make a decsion afterwards. Zack and Jessie go and spy on them dressed up as old ladies. At first they cant tell what going on but when Jennifer goes to whisper into Slaters ear, Jessie walks off disgusted thinking that she just saw them make out, which in reality wasnt the case. Fast forward to The Max where the four of them encounter each other. Both Slater and Jennifer agree that its best if they just stay friends which leads to a jubilated Jessie and Slater. Also Zack tries to pull his charm on Jennifer which concludes the episode.