Julien finds a bag of coffee beans in the Cove of Wonders and gets the entire lemur community hooked on caffeine.
At the Cove of Wonders, Julien is interrupted by Maurice, who is complaining about Julien's royal to-do list. Julien "forgives Maurice for not doing his duties" despite them being Julien's duties. Julien reels back Mort, Maurice asking why Mort is tied to his fishing line. To answer, Julien shows Maurice a bag in the water, with the words "king" and "magic" on it. Julien casts Mort out again and tells him to retrieve the bag. Mort grabs the bag, but gets swallowed by a crocodile. Julien and Maurice reel Mort back, freeing him and the bag. Julien pads up to the bag and pulls out some beans. Still thinking it's magic, Julien eats the beans, but soon starts choking on them. Maurice and Mort get the beans out of him as Julien says the magic isn't working. Mort points out to Julien that there are instructions on the back of the bag. Julien sees it and thinks the picture is a key to unlock the magic, and he just knows who might have one of the juicers pictured.
Julien brings the bag to Timo and asks for a tool for the coffee beans. Timo builds the coffee maker for Julien, and says it may either work or explode. Julien takes the risk and Timo starts the machine, and it makes coffee. Julien drinks the first cup, but his tongue starts burning. After his tongue cools, Maurice asks if he feels anything. Julien doesn't, and questions what went wrong. Timo suggests the mixture might need adjusting, more or less. Julien, after hearing more, drinks the rest of the coffee. Julien begs the gods to give him powers of any kind, and starts crying. Maurice turns Mort and Timo around to give Julien some room, but when they turn back around, Julien has bolted out of the room.
With more speed and lots of energy, Julien blazes through his to-do list during the rest of the day. At night, in the plane, Clover and Maurice enter to Julien reading. Clover asks if he has slept. Julien says he has not, since he got so many things done, and throws Maurice his completed to-do list. Maurice, surprised, says this is incredible. Julien replies that it's coffee that brought out his potential. Clover makes a comment about how if this drink is real, she would be able to make the kingdom crime free within a day with a cup. Julien, after hearing this, gets an idea.
Beneath the tree, King Julien gathers the kingdom and introduces them to coffee, which he has renamed Brown Julien. When no lemurs volunteer to go first, Julien volunteers Clover. After drinking six cups, Clover becomes hyper and bounces through the trees. The lemurs are now hook on to the idea of coffee, and all rush to grab a cup. Maurice is still not sure that no sleep is a good idea, but Julien rubs it off and gives him and Mort a cup. The kingdom goes through a period where everyone is hyper and full of energy, to a slowed down and addicted period. Timo tells Maurice and Clover they're out of Brown Julien. Clover tries to shout but Maurice tells to keep the information on the down low to avoid crazed lemurs.
Maurice and Clover walk in to see Julien exhausted on his throne. Then, Mort comes in, intelligent with an accent. He explains that coffee increased his intelligence, and what Julien needs is simply more coffee. Maurice says that is a problem since the kingdom is out of coffee. This wakes Julien, who complains about his headache. Smart Mort explains that Julien's brain is drying out from the lack of coffee. Maurice tells Julien to keep it down, because the lemurs outside the plane can hear in, and they start to threaten Julien.
A calming voice is heard, telling the lemurs everything is going to be all right. Julien looks, and it is Karl. Julien asks why he's here, since he was defeated the last time, and Karl explains he has a plan to defeat him, which is working perfectly. Maurice asks what the plan is. Karl says it is a plan to bring the lemur kingdom to its knees with a cup of coffee. Karl had Chauncey watch Julien's every move, and trained crocodiles to take coffee beans to the Cove of Wonders, knowing the word "king" will make Julien take the bait. Julien bites back that Karl's elaborate plan doesn't make sense. Karl counters that it does, since his kingdom now has coffee cravings, and need coffees. Coffee that he has. Karl snaps his fingers, and rats appear, giving the lemurs coffee. He demands that Julien is removed as king, in return, he will supply the lemurs with Brown Julien. Julien says his plan failed because his people wouldn't choose Brown Julien over him. The lemurs think about it and kick Julien, Clover, and Maurice out of the kingdom.
Julien is mad that his people chose coffee over him, but is glad Maurice and Clover are with him (although, as Clover points out, not by choice). Smart Mort appears from the bushes saying he'll always love King Julien. Smart Mort gives Julien and Clover two cups of coffee he made. When Maurice asks how they'll get the kingdom back, Smart Mort suggests they find Karl's supply of beans. He asks Julien if he would know where Karl's coffee fields are. Julien remembers that Karl appears in his bed to talk about his parents' poo coffee business. Maurice figures out from Karl's parents' poo-coffee business that there's only one part of the island to grow coffee.
The group arrives at Karl's poo-coffee fields, worked by rats. Julien comes up with a plan to break Karl's hold on his people by taking his coffee-fields. Smart Mort says he will take care of the rats. Smart Mort walks through the fields as the rats threaten him. Smart Mort calmly says they can eat him, but are they happy with their health care benefits?
At Karl's lair, Clover notes the door's lock can take hours to open, but Julien claims he has a better plan. Julien knocks on the door and says there is a package for Karl. The rat on guard says they only open the door for emergencies. Julien says its an emergency and the rat opens the door and gets knocked out by Clover. Clover comments that the place looks deserted, but Karl appears, he knew Julien would come for his fields. Karl pulls a switch and rats come in. Clover beats the rats up, and Julien says he hopes Karl is applauding his own downfall. Karl asks if Julien knew he had a backup plan, and the entrance closes as the ceiling opens, with rats coming in. Karl gloats this is Julien's end, and no floating balloon will save him. The door behind him slams open, knocking Karl towards the wall. When Karl asks who has done this, Smart Mort appears with the rats on strike. The rats ask for a working wage and retirement plan. King Julien offers the rats money, a competitive rate, and stock options if they take out Karl. The rats surround Karl, angry.
Julien, Clover, and Maurice look over the coffee fields. Clover asks where Smart Mort is. They find Smart Mort with Karl stepping on his tail and a laser pointing at him. Smart Mort apologizes because he got distracted by the thought of feet. Maurice asks how Karl got past the rats. Karl explains rats don't know what a stock option is, and offered them something they know: "free bagel Fridays every other month". Karl points the laser at Julien to incinerate him. Smart Mort bites Karl's foot, causing Karl to drop the laser. Smart Mort tells Julien to get the weapon before being grabbed by Karl. Julien grabs the weapon and points it at Karl. Karl tells Julien to put it down or he'll end Mort with his claws. Smart Mort tells King Julien to take the shot, while regular Mort tells him not to. Julien says goodbye to Smart Mort and fires the laser at the coffee fields, incinerating them. Karl throws Mort/Smart Mort away and sobs that his brother Bruce is going to kill him when he gets back. Clover goes to Smart Mort and realizes that without coffee, Mort will be stupid again. Smart Mort shrugs it off, saying he's been stupid before. He then goes back to regular Mort and puts a fruit hat on his head. Maurice congratulates Julien for making the right decision for Mort and the kingdom, and says they'll be fine without coffee. Julien says to tell that to his headache. Juilen gloats to Karl that his evil plan has failed again. Karl retorts that Julien is a brilliant and worthy opponent. Karl continues that there will be more evil plans, and tells Julien that the laser takes several minutes to recharge. Karl grabs onto a ladder, on a balloon piloted by Chauncey. Karl yells to Julien that it isn't over, "not yet at least". As the group walks away, Mort grabs on to Julien's feet and Julien sighs that he misses Smart Mort already.