It's Bunsen's first day of school, and Amanda feeds him beats, turning him into a monster. Bunsen, Mikey and Darcy must retrieve Bunsen's body before an evil beast's head takes control of it.
Bunsen proves bees are the best spellers when he turns into one and wins the spelling bee. When MMA fighter, Jerry The Beast, picks Bunsen to be his new mascot, Mikey has to prove that he is a beast too.
After discovering Bunsen's uncle in a museum, Bunsen and Mikey try to sneak him out before Amanda catches them. After Bunsen sprays himself with fancy body spray, he transforms into a hunk and becomes Amanda's desire.
It's teeth losing season for Bunsen, and having so many teeth, Mikey explains that Bunsen will be richer than Amanda once the Tooth Fairy leaves him money for them. To prevent this, Amanda vows to capture the Tooth Fairy.
It's Bunsen and Cosmo's Friend-iversary, so Bunsen excitedly takes Mikey to meet him in Dimmsdale, while Amanda secretly follows. The group has a great time, until Mr. Crocker and Amanda team up and decide to take them down.
When Amanda learns of Bunsen's strong fear of thunder, she devises a plan to scare him out of Muckledunk. Bunsen wants to win pies for Mikey, but Bunsen starts to lose his memory after getting a case of the hiccups.
It is the beast holiday, Beastgiving, so Mikey helps Bunsen deliver dream gifts to the citizens of Muckledunk./Bunsen's internal clock gets thrown off during daylight saving time.
Bunsen tries to help Mikey overcome his fear of the woods during an overnight camping trip. Amanda tries to sabotage Mikey and Bunsen after they are appointed the new hall monitors.
On a fieldtrip to MASA, Mikey and Bunsen run into Commander Cone, mistaking him for a Mastronaut. Not wanting to disappoint his young fans, Commander Cone gives them a tour of MASA and accidentally launches them into space.
Amanda turns into a ferocious beast and causes panic at school after eating Bunsen's beast cookies. Mikey, Bunsen, and Amanda team up to study minks after Amanda's tightened braces causes her to make mink calls.
Amanda gets trapped in Bunsen's hugging chair and can only be released once she is happy. Bunsen falls in love with a guinea pig and tries to woo her, while Amanda tries to sabotage the love affair.
To make time for their band, Mucklefunk, Bunsen clones Mikey so his clones can run all of his after-school clubs.NLMikey and Bunsen go into detective mode after Commander Cone is framed for stealing Amanda's phone case.
Bunsen's Beast Ball tells him and Mikey to do fun things, until Amanda swaps out their Beast Ball for her own. Mikey wants the lead role in a play so he can get a kiss from Sophie Sanders, but Amanda plans to sabotage that.
Mikey and Bunsen help Amanda pass the Preparatory Overview Of Pupils test so she can avoid summer school. Mikey enters Bunsen into the Muckledunk Mutt Show, but Amanda tries to sabotage them and win with her robot dog.
Mikey and Bunsen have to deliver a beast baby after accidentally switching packages at the Monstork Factory. Bunsen's cousin, Wilda, comes to town and develops a crush on Mikey, which terrifies him and makes Amanda jealous.
It's Bunsen first Halloween and Mikey is excited to show him how to collect tons of candy, but Amanda plans to dress up like the Sweet Teeth beast and steal everyone's candy for herself.
Bunsen is super excited about celebrating his first Christmas ever. But when Amanda finds out she's on the naughty list, she stuffs Santa in a gift box and hijacks all the toys. Can Mikey and Bunsen find Santa in time to save Xmas?
Amanda becomes Mikey and Bunsen's best friend after they perform the Best Friends Forever beast ceremony. Amanda sends Bunsen and Mikey on a bogus treasure hunt by giving them a fake map to Captain Schnook's Booty.
Mikey and Bunsen have to find Boodles, Bunsen's invisible dog, after Amanda lures him away from home. Bunsen's best friend Wolfie comes to visit Muckledunk and has his eyes and stomach set on Mikey.
Mikey and Bunsen are forced apart after Miss Flap changes the seating chart to mix things up. When Bunsen is hypnotized by swirling toilet water, Amanda tries to convince him to return to Beast World.
When Bunsen eats Amanda's universal remote, he and Mikey have to rescue her from her malfunctioning smart house. Mikey and Bunsen compete against Amanda for the chance to have their own segment on the local news channel.
Mikey discovers that Bunsen is about to hibernate for 50 years! The only way Mikey can save Bunsen is to keep him up past his appointed hibernation time. Mikey and Bunsen go on a shopping spree adventure at "I've So Gotta Have It" store.
Mikey and Bunsen use Boodles' fur to turn invisible and sneak into a scary movie they're too young to see. Mikey and Bunsen try to help their hero (the local ice cream delivery guy), Commander Cone, find his dream job.
