Gosalyn is showing off her prodigious board game skills, soundly defeating Drake at a monopoly-like game. a pan frame shows it is the most recent of dozens such games.
Gos retreats upstairs where it is revealed that she has "called in markers" on Launchpad, making him pay off board game gambling debts to her by cleaning her room and doing her homework. Drake confronts her on the amoral behavior, but is interrupted by an alarm from D.R.A.T., his latest gadget. It alerts the gang, in a roundabout way, to a crime in progress by Bushroot. Gosalyn demands to go along, but is kept out of the loop by Darkwing and Launchpad.
Spoiled for intelligent conversation, Bushroot is working on a new experiment to create a plant intelligence enhancer via IQ2U. Unfortunately it is ineffective, reducing a target hedge nothing more than an insensate drooling beast. Darkwing shows up, spoiling further experiments, and apprehends Bushroot. At that moment though, Gosalyn appears, intending to help out, only to end up freeing Bushroot and Spike and spilling his experiment in the process.
When they return home, Drake intends to resume his talking to with Gosalyn about her board game morals, only to find that she has begun to mutate into a horrible slime creature. Multiple experiments in Darkwing Tower fail to cure her, and the Drat sounds again. after hours of complex calculations, the evening newspaper reveals that Bushroot has struck again. Gosalyn insists on helping out, dubbing herself YuckyDuck!
Darkwing again tells her to stay home. He and Launchpad track down Bushroot and Spike in the company of a giant mutated hedge. But Yucky Duck shows up, saves them, and sends Bushroot running. Far from grateful, Darkwing chastises Gosalyn for endangering herself and others. This drives her away, and into the arms of Bushroot who embraces her as the intelligent plant friend he has been striving for.
Back at Darkwing Tower Darkwing Duck continues to try to find an antidote for Gos's condition, only to find that the plant serum has a number of affects, ending in death by gooification. At the same time, Bushroot is trying to figure out how to reverse engineer Yucky Duck, only to notice the same side effects. Saddened, he sucks Gosalyn into a containment chamber and continues his research.
Darkwing shows up, and as the struggle, Launchpad tries to free Gosalyn, only to end up inside the container with the much diminished gooey girl, who by now can only speak single-word phrases. an accident causes Spike to gain the newest version of the IQ2U formula, and in a fit of jealousy he buries it in the garden, resulting in the lawn coming to life.
Darkwing reluctantly admits he needs Bushroot's help to defeat the animated lawn, which Bushroot misinterprets as friendship. Using Bushroot, DW finds a herd of sheep which consumes the lawn. Unfortunately, DW finds Gosalyn and Launchpad still trapped, with Gos on the verge of final decay. In frustration bemoans his fate, unable to help his daughter. Bushroot intervenes, flipping the switch which frees Gosalyn and Launchpad from the container.
Darkwing tries to encourage the mutant plant-duck to flee custody while he has the chance, but Bushroot is too dense to take the hint, resulting in DW shoving him out the door, to be followed by the loyal Spike. DW makes observations on the true meaning of friendship, and takes Gosalyn home to the house to cure her.
It turns out that despite all Darkwing's and Bushroot's chemical experiments, the cure for IQ2U is plain old soap and water and a vigorous scrubbing, much to Gosalyn's disgust as she is bathed by her dad.
- First Appearance of the D.R.A.T. computer.
- One of the few episodes where Darkwing loses a collar, letting Bushroot escape in exchange for his help in curing Gosalyn.
- Gosalyn displays a new and unique talent, not only is she a videogame queen, but she is undefeated in the Mallard household in any and all board games.
- Another of Gosalyn's "costumed" adventures with Darkwing, see also Quiverwing Quack, Crimson Quackette, GozmoDuck, The Grubb, and the True Outdoors Person.
- First St Canard radio station, KRYM "All Crime All the Time". Second is KDUQ, which was stolen by Moliarty to power his Kinetobeam.