"My child, we can no longer live as rats. We know too much."
This page is about the animated film The Secret of NIMH. If you are looking for the article about the book or its literary sequels, see Mrs. Frisby and the Rats of NIMH.The Secret of NIMH is Don Bluth's first feature-length film; it is based veryloosely on Robert C. O'Brien's Newbery Medal Award-winning novel Mrs. Frisby and the Rats of NIMH.Mrs. Brisby is a widowed mouse and mother of four living near a farm. With spring fast approaching and the frost melting from the ground, her family has to move in order to avoid the farmer's plow — but one of the children, Timothy, has come down with pneumonia and can't be moved for a few weeks. Taking the advice of an all-knowing owl, Mrs. Brisby seeks the aid of the Rats of NIMH, a group of escaped lab rats that were rendered super-intelligent via experimental drugs. After meeting with the rats' leader, Nicodemus, Mrs. Brisby finds out that her late husband Jonathan had been a good friend of the rats — and died while helping the rats carry out a plan to leave the human world behind. Nicodemus agrees to help Mrs. Brisby move her home, but some of the other rats have plans of their own...The Secret of NIMH was Don Bluth's first feature film after leaving Disney; it was even produced a decade after Disney itself had turned down adapting the original story. Bluth used traditional tools and methods as a way of fighting back against the movement towards lower production costs (and lower quality animation). The film was commercially a moderate box office success, costing $7 million and earning $14 million; this modest revenue was, in part, due to competition with E.T. the Extra-Terrestrial. However, The Secret of NIMH was well received and managed to seduce the very director of E.T. the Extra-Terrestrial, Steven Spielberg, who would later offer himself to team up with Don Bluth, and together they would make the high-grossing films of the '80sAn American Tail and The Land Before Time.The Secret of NIMHhas come to be regarded as a masterpiece of animation in the years since its release, with many animation enthusiasts and film critics regarding it as Bluth's best work. The film was released on DVD twice — once as a single-disc with no special features, and once as a two-disc "Family Fun Edition" that included a feature-length commentary from Bluth himself — and 2011 saw a Blu-Ray release for the film.Years after the original film, a Direct-to-Video sequel called Secret of NIMH II: Timmy to the Rescue was released. The film was (predictably) produced without Bluth's involvement.
The movie series has examples of the following tropes:
Adaptational Comic Relief: Jeremy, a minor character in the book, has a larger role as the main comic relief in the film. His traits such as attention to shiny things and looking for romance are Played for Laughs, unlike in the book where he was younger and more of a 'na´ve' character. He also becomes a Cloud Cuckoolander and a Butt Monkey. This provides a contrast to characters such as Jenner and Nicodemus, who are played much more seriously than in the novel. A few years after the film's release, the original author's daughter Jane Leslie Conly wrote two sequels which incorporated Jeremy's more absent-minded personality.
Artistic License - Biology: The injections administered to the rats in the NIMH flashbacks are much, much too large for a one-pound rodent to receive without dying of heart failure. The proper veterinary dosage for such tiny animals' injections has a volume of a fraction of a mL. However, this may just be the rats' imagination, seeing as the lab also looks quite unsanitary.
Awesome but Impractical: The ink Nicodemus uses to write in his journal in the opening scene. It sheds golden sparkly fairy dust all over the place, and the text he writes doesn't become visible until after a two-second delay.
Butt Monkey: Jeremy, a lonely compassionate crow who just wants to help out and find love; unfortunately, he is also a hapless klutz, tending to cause more problems than he solves. He's constantly reprimanded by Mrs. Brisby until she eventually gets rid of him by having him see to trivial minor duties, both of which he fails miserably with too. He does at least get his "Miss Right" at the end of it though.
He and Cecil retain this role in the sequel, albeit toned down somewhat; this is likely due to the zanier setup (Jeremy at least seems to have warmer relations with the characters, especially Timmy).
Mrs. Brisby acts somewhat as one in more comical moments, though probably leans more towards woobie territory.
Cats Are Mean: The cat in question is namedDragon. Invoked again in the sequel with Muriel and Troy, the two alley cat minions (albeit in a more pitiful sense). It is refreshing change in that this cat who acts just like a cat is considered bad, but doesn't get an undeserved comeuppance.
What is very interesting about this is that, in the scene where Mrs. Fitzgibbon is hanging out the laundry and Dragon is sleeping near the back step (a scene which takes more of an omniscient camera view than the first-person view of the mice), he doesn't come across nearly so horrifying. Part of this may be due to him being drugged at the time, but it also comes across as him seeming a normal cat here but a monster in all his other scenes because that is how a cat would look and sound to a mouse. (See Translation Convention.)
Inverted in the sequel. Muriel and Troy are actually brainwashed by Martin to do his evil bidding, and are suggested to be the only villains that don't escape the fire and thus possibly meet their demise.
Cloud Cuckoolander: Jeremy isn't the most stable of characters sometimes. Martin under the influence of NIMH's experimentation in the sequel may count as a villainous example.
Conspicuously Light Patch: While the characters' fairly straightforward animation is understandable in contrast to the sumptuously painted backgrounds, when something in the background needs animating, it can be rather jarring. The mud sloshing around the Brisby's house as they're trying to move it is particularly obvious.
Crouching Moron, Hidden Badass: Jeremy spends most of both films irritating the other protagonists with his clumsy behaviour. However, he is a graceful flyer and counts as the only character in the first film to outright attack Dragon to save Mrs Brisby.
Jenny plays this trope hard on occasion in Timmy To The Rescue.
Justin also does this in one moment of the first movie.
Jenner: (He's been talking about how Nicodemus's plan to move the rats shouldn't be done) We were just talking about you.
Justin: Well that's refreshing Jenner, usually you're screaming about us.
Disneyfication: Averted somewhat. While the movie has some traditional changes from the original book (eg. more whimsical and slapstick-esque characterization and dialogue), some aspects are actually darker compared to its original material. The death count of pivotal characters is higher in the movie, for example. The sequel plays this straight, complete with musical numbers and numerous comic relief extras.
In a way, this trope is double subverted; while Mrs. Brisby goes through much more hardship than in the book, this allows more emphasis on the power of courage and love. The theme was absent in the original book in favour of a greater focus on the rats' responsibility to stop stealing (which was itself mentioned in the film, although it was more about the moral issues of stealing rather than the practical ones).
Disney Villain Death: Averted, though the villain still falls. Jenner dies in full view, as well as his (former) henchman Sullivan. Sullivan throws a dagger into Jenner's back before dying of a sword wound. They ain't comin' back.
Arguably Muriel and Troy in Timmy To The Rescue falling down an elevator shaft. The tone of this is comical, though the fact they aren't seen escaping as NIMH as it is set ablaze leaves suggestion whether they survived.
Evil Sorcerer: While his powers are all based around technology, Martin of The Secret of NIMH 2: Timmy To The Rescue certainly seems to enjoy the trappings of this trope. Complete with robe and staff.
The rats don't seem to hold any real grudge against humans in general, preferring to simply avoid them. When Nicodemus reveals the rats' story and the nature of the Plan, he makes it clear that stealing food or electricity from the humans is wrong.
The one human who directly encounters Mrs. Brisby actually goes out of his way to save her from the cat, and puts her safely into a cage with food and water. Not so bad, considering how mice found loose in people's houses are usually dealt with.
Jerkass Fašade: Brutus, the huge intimidating guard to the rat's hideout, is revealed as such in the original novel. The original film, which makes him far more intimidating, at first only vaguely hints to this ("Oh, that's just Brutus..."), but he does try to help pull up the Brisby home; you hardly see him, and wouldn't know it was him if Justin hadn't called out his name, but he's there.
Justin: I'll get a line around the stones, now...Brutus, quick! Get some rope; tie off those block lines!
"Auntie" Shrew. She is first introduced as a pish-posh busybody who walks around with an incredible air of self-importance, but she soon demonstrates great bravery by warning all the animals about the plow and rescuing Mrs. Brisby from the tractor.
Mr Ages is for the most part a cranky, unsociable hermit though he nevertheless assists Mrs. Brisby with every plea she makes to assist her family plus is revealed to have been quite the badass himself, being the one previously tasked with drugging the cat before he injured his leg, as well as playing a part in the rats' escape alongside Jonathan Brisby.
Cecil the Caterpillar; despite being a con-man and a bit on the cowardly side, he goes out of his way to help out the protagnists with little motive. He is introduced saving Timmy and Jenny from an eagle.
Mind-Control Eyes: Jeremy after glancing at Mrs. Brisby's "sparkly" in the original. Evil!Martin also shows an occasional gaze of these in the sequel, for relevant reasons.
Mouse World: Several, designed by the rats and mice of NIMH.
Never a Self-Made Woman: Mrs. Brisby would not have gotten any help for her situation if she wasn't "Mrs. Jonathan Brisby".
Only One Name/Last Name Basis: Mrs. Brisby is never referred to as anything other than Mrs. Brisby. The closest they get to giving her a first name is calling her Mrs. Jonathan Brisby, but that's referring to her husband.
Shoo Out the Clowns: In both movies, the comical Jeremy more or less disappears halfway through until the main climax is over. Cecil the Caterpillar is taken out briefly in the sequel as well, though does get some involvement in the final action (see above).
Actor Allusion: Jenner's death is similar to Tony Montana's: both characters are hit in the back and then fall face down into a pool. Paul Shenar, who voices Jenner, played Alejandro Sosa in the same movie.
Actual Pacifist: Sullivan, Jenner's ally on the council of the rats. Jenner hatches a plan to murder Nicodemus and make it look like an accident with Sullivan's help, but Sullivan wants to back out at every step of the way and abhors the idea of killing. Eventually he redeems himself while dying by throwing a dagger into Jenner's back.
Jenner: No taste for blood, eh? They've taken the animal out of you.
Adaptation Explanation Extrication: The sequence in the book where the rats are taught how to read is overlooked in the film, making it look like the injections alone gave them the ability.
Adult Fear: It's scary enough for the single mother Mrs. Brisby having to deal with her critically ill son, but during the climax when her children are stuck in their cement block house and it's sinking into the mud the fear is amped up ten-fold.
Age Lift: Nicodemus was middle-aged in the book. In the film he is very old-looking, considering the injections given to the rats slowed their aging.
All-Powerful Bystander: Nicodemus is quite adept at scrying and can see Mrs. Brisby's dilemma and is ready to help her before she even goes to consult the Great Owl. Why he doesn't just save time by sending for her immediately is never addressed. Justin knew Jonathan Brisby and considered it an honour to meet his wife, so he could have invited her to the rosebush. Even Mr. Ages despite his normal grumbling nature would have been up to the task, considering he was all for helping her during the council session. The only plausible explanation is that Nicodemus couldn't risk extending his hand to Mrs. Brisby first while the Thorn Valley plan was still being debated for fear of his political enemy Jenner accusing him of going soft or senile or mad and using it as an opportunity to gain power.
Arc Words: "Courage of the heart is very rare / The stone has a power when its there".
Avoid the Dreaded G Rating: Don Bluth and company attempted to get NIMH a PG rating to have it appeal to a larger audience (the film definitely isn't very kid-friendly): there was a superfluous (though understandable given the circumstances) "Damn!" spoken by Justin, several on-screen deaths, visible blood, and a fair amount of nightmare-fueling scenes. For reasons beyond all understanding, the MPAA still gave them a G. One would almost have to assume they didn't bother to watch it.
Badass Normal: Though the rats are no less frightened of Dragon than are the mice, rats are too large to get into the house to drug him, leaving the mice to do it. Jonathan dies in one attempt (in his defense, he also did it countless nights forfour years before finally being caught), and Mr. Ages breaks a leg in a subsequent one. Both are genetically modified, but Mrs. Brisby is the one who succeeds with just a scratch.
Nicodemus, full stop. His eyes always glow. It's never explained why.
The Great Owl's eyes are exactly the same. Glowing eyes seem to be associated with great age and wisdom and some kind of unexplained power. Another reason why The Great Owl is certifiably Rule of Cool incarnate. He's even voiced by John Carradine!
Lampshaded: "Owls eat mice!" "Uh...only after dark." There are bones strewn about the Owl's lair. Owls compact all waste into a pellet-like solid, bones and all (though these are probably from disintegrated pellets; the Owl isn't too concerned with tidying his lair). The Owl seems to be completely nonplussed by this mouse but he'll gladly eat a passing bug.
A more standard example is the fact that Mrs. Brisby is friends with a shrew. Shrews eat mice.
As do crows.
As do rats, under normal circumstances.
Every non-relative she has a conversation with in the entire film would've tried to eat her in Real Life, except Mr. Ages. He might've eaten her kids if he was hungry enough.
Cold Open: The film starts with Nicodemus recording in his book about the death of Jonathan Brisby, and putting away a red medallion while talking to John in spirit. Obviously, this proves to be important later.
Didn't Think This Through: Jenner's plan is clever in theory: destroy the Brisby House and kill Nicodemus so that the rats are stuck on the farm and he can become their ruler. The flaw in the plan is that he won't be able to rule them for very long because soon the rosebush will be destroyed and they'll all die. Not such a Magnificent Bastard after all?
It's not so much he didn't think of that problem, as much as he so stubborn (and somewhat unhinged) in his efforts that he refused to believe it when warned.
Dragon, the farm cat is truly monstrous and feared by all the woodland animals save for the rats who know how to pacify him.
The Great Owl is this towards the woodland animals, for obvious reasons.
The rats of NIMH who live in the rosebush are this to some of the woodland creatures, especially Auntie Shrew. The same Auntie Shrew who single-handedly faces down a tractor and wins, later tells Mrs. Brisby to show courage in asking an owl for help, and captures and ties up a crow, visibly panics at the sound of the rats arriving.
Faux Affably Evil: Jenner is possessed of a singular charm and charisma that makes it easy to see how he manipulates others around him. However, almost all of his charm and courtesy towards others is solely to meet his ends, and when things start to turn against him he devolves into a feral creature, and there is no one he won't kill in cold blood to keep his plan in motion.
Flat Character: Timothy in the first film; he has exactly one line of dialogue, and is little more than a bed-ridden plot device that gives Ms. Brisby a reason to go on her adventure.
Four Lines, All Waiting: There are at least four ongoing plots tied together in the original film—Ms. Brisby trying to save her children from the farmer's plow, the Rats of NIMH trying to leave for Thorn Valley, Jenner trying to sabotage their moving plans by murdering Nicodemus in a staged accident, so in turn he can usurp leadership of the Rats of NIMH, and Jeremy the Crow trying to find a love interest. And if you count the tiny subplot of the farmer interacting with people from NIMH who are searching for the rats and plan to destroy them, that's a grand total of five. Surprisingly, the sequel directly followed up on that last plot thread.
Furry Confusion: The Rats angst over this quite a bit. Though, looking at the farm animals, all of them show intelligence and act somewhat like humans — to a point. Only the insects play fully realistic parts.
Jenner devolves into an animalistic rat during his fight with Justin for a brief moment.
GASP: Brisby does this when she sees bones from the Great Owl's previous kills falling after she slips on some.
Giant Spider: In the Great Owl's lair, before it's crushed to a to pulp.
Glowing Eyes of Doom: Subverted. Although two characters look evil and have glowing eyes, they do no harm to anyone.
Good Is Not Nice: Mr. Ages and Auntie Shrew are both rude and haughty at the best of times, but are also amongst the most courageous characters next to Mrs. Brisby herself.
Gory Discretion Shot: Both played straight and averted. While Nicodemus's death occurs off-camera, we see the owl causally devour a still-living insect, Mrs. Brisby's cut (hey, it's a G-rated movie, any blood is gore), two characters stabbed, and some rather graphic depictions of animal experimentation, even if only for a few seconds.
Technically, we do see Nicodemus get hit pretty hard with a pulley and knocked off the rock, which may have killed him before the block did.
Dragon as a troll/griffon/other fantasy monster, not too bright but cunning, the primary local hazard.
Jenner as the ambitious nobleman, scheming to turn the situation to his advantage to kill Nicodemus and take his throne...
Nicodemus as a powerful mage, a literal Wizard King, and secretly aligned with...
...the Great Owl as the real dragon, an ancient, cave-dwelling "Great Wyrm" that offers Mrs. Brisby salient advice at Nicodemus' behest...
.. and so on.
Humans Are Cthulhu: Debatable, but humanity does seem pretty Cthulhuish in several respects here. In particular, the Rats of NIMH are understandably terrified of what humans would do if they found a society of transgenic sentients living in a rosebush in some farmer's front lawn. Makes more sense in the context of Heroic Fantasy, above.
Identical Stranger: Despite being different species and knowing each other, Nicodemus and the Great Owl have the same glowing eyes, same big eyebrows and same-length moustaches. See picture above.
Word of God: Don Bluth mentioned that they were meant to be mirror images of one another; both "godlike" in their own realms and thus styled very similarly, which would explain the close alliance they had.
Leave Him to Me: Jenner pulls this, as he wants to crush Nicodemus under a hoisting crane. Oddly, this is done as a murder plot and not (as it usually is) during a heated battle. He also says this word-for-word when Sullivan asks him what to do about Justin.
Ludd Was Right: The Rats of NIMH angst over their dependence on electricity, as they must steal it from the farm. The whole plan to move to Thorn Valley hinges on their becoming entirely self-sufficient. It's not that they don't like technology or advancement; stealing electricity from the humans just is dangerously conspicuous activity for hyperintelligent rodents on the run. That and they're starting to gain some human-like morality and deeper emotion, such as the feeling of ennui as they realize that a life living entirely off the back of another was robbing them of self-worth.
Magitek: The rats' technology is human artifacts, mixed with Nicodemus' technomagery.
Mama Bear: Not as violent as standard examples, but any mouse (especially a semi-anthropomorphic one) who'll enter the dark spooky lair of one of her natural predators, in order to save her children, deserves a mention.
Meaningful Name: Farmer Fitzgibbon, as in "son of an ape". Not helped by the fact that the prefix "fitz" was, in medieval times, widely used for the surnames of acknowledged illegitimate children - thus making it into "bastard son of an ape". Which is far more insulting, when you think about it.
Minion with an F in Evil: Sullivan doesn't really do anything to further Jenner's plots. He can't bear the thought of killing Nicodemus and refuses to swing his sword at the crucial moment, leaving Jenner to do the dirty deed. He even tries to stop Jenner from going over the edge and gets his throat cut for his troubles. He lives just long enough to redeem himself by stabbing Jenner In the Back before he kills Justin.
Mr. Exposition: Nicodemus, but he actually does it well. Mr. Ages and Justin too.
Never Say "Die": Averted, consistently, in that even the youngest characters confront death head on and discuss the possibility openly.
Nice Hat: Invoked by Jeremy ("Oh, what a lovely hat!") to Auntie Shrew when trying to sweet talk her.
No Control Group: Averted; in the flashback, when Nicodemus escapes from his cage, the row below his are clearly marked "CONTROL GROUP" (though this was hard to make out in the VHS version). The book more clearly mentions them. In the film, they're using wild-caught specimens, which rather negates the control group in Real Life with lab animals that you can buy from breeders. (Yes, there are purebred lines of lab rats and mice.)
Explained a bit better in the book, as domestic lab rats are reared in plain cages and thus don't get the mental stimulation that wild ones do. Using wild-caught rats for both the experimental and control groups gave the researchers' subjects an intellectual head start, even before being injected with brain enhancers.
Not Now, Kiddo: Auntie Shrew won't listen to the youngest Brisby child when she tries to tell her that her brother is sick.
Off Model: During Nicodemus' "We Know Too Much" speech to Ms. Brisby, at one part his eyebrows inexplicably disconnect from his head for a few frames!
Older Than They Look: Nicodemus mentions to Mrs. Brisby that the genetic manipulation slowed their aging process, and that Johnathan would have continued to live on and still look young while she grew old.
Papa Wolf: Jeremy tries to act as one, but ultimately his clumsiness intervenes — as well as inadvertently falling under the wrath of a Mama Bear in the process. That said he does act out a pretty valid showing of this for Mrs. Brisby, and to a lesser extent, Timmy.
Power Strain Blackout: Mrs. Brisby, immediately following the film's climax, wherein she uses The Stone for the first and only time to move her home. She collapses as its power subsides, then passes out.
Also much of the fight between Justin and Jenner is filmed/animated in reddish hues.
Red String of Fate: This may or may not be an intentional usage; when Mrs. Brisby first meets Jeremy, he is tangled in red string, which he is retrieving to build a "love nest" for his future "Mrs. Right".
Played straighter however in that Dragon is a little too big for even a good-sized housecat, being closer in size to an almost medium-sized dog.
Schizotech - crosses over with Hammer Space when Justin and Jenner pull out their swords. Considering that the rats adapt human technology based on their functioning understanding of it (well, at least in the novel), one might wonder where they managed to come up with the idea that full-on medieval swords in tiny miniature version would be a good idea. Especially considering the kinds of heat needed to shape metal when they live in a flammable environment (it's a rose bush). In any case, for some this might lean into Fridge Logic country, and for others it leans in the opposite direction, however you can't deny that the combination of electricity, elevators, lighting... and magic and swords is a little schizoid.
Possibly the swords are justified, as the rats did need some means of defense against predators such as snakes or weasels. While they probably had the know-how to build firearms, those would be too noisy for creatures that live in hiding.
It also goes right along with the idea of the whole thing being a Heroic Fantasy; of course our medieval warriors would have swords, the rest of their technology being Magitek.
Ship Tease: Justin and Mrs. Brisby flirt a bit over the course of the movie, but both have more important things on their minds.
Shout-Out: Ms. Brisby raising her house with the medallion at the end, at least how its visually presented, is very likely a homage to Yoda using the Force to raise Luke's X-Wing in The Empire Strikes Back.
Spared by the Adaptation: Justin, who becomes the leader of the rats after Nicodemus' death. Justin supposedly died in the novel by getting poisoned by NIMH.
Jenner: The Thorn Valley Plan is the aspiration of idiots and dreamers! We... (sees Justin and Mr. Ages and chuckles) We were just talking about you...
The Greatest Story Never Told: In the movie, how the uplifted mice and rats manage to make their way out of the labyrinthine building their lab is in. The book describes their escape in detail; the movie limits it to a couple of brief scenes (albeit one that's pure, distilled Nightmare Fuel).
Translation Convention: In an interesting variation, Dragon's meows are rendered (except in a brief scene centered on the humans) as horrific, dragony roars to reflect that, as far as his prey is concerned, he lives up to his name.
Possibly justified, as mouse ears are attuned to higher-pitched sounds than humans. A cat's yowls could quite plausibly be at the far low-frequency end of Mrs. Brisby's range of hearing, even though they'd sound high and plaintive to humans.
In the scene when Mrs. Brisby is imprisoned in the cage, and Mrs. Fitzgibbon goes to let Dragon in the back door, we hear him make perfectly normal feline meows. Like the scene where she's hanging the laundry, this moment is shown from more of an omniscient viewpoint than Mrs. Brisby's first-person angle, suggesting we're not seeing things from a mouse POV anymore.
Truth in Television: The research lab the rats and mice break out of is based off the real-life National Institutes of Health Building 10◊, the largest hospital in the U.S., where all their clinical trials (and many animal labs) are located. The picture shows about a quarter of the building; it's as big as a city block, and people get lost in there routinely. Try to imagine escaping from a building that size if you are a rat or mouse...
Villainous Breakdown: Jenner spends most of his time in the film being a Faux Affably EvilSmug Snake. When it looks like his plans have come to fruition near the end once Nicodemus is dead, Mrs. Brisby comes to warn the rats of their impending demise at the hands of NIMH. Jenner is so frustrated that he loses all semblance of civility and attacks her, trying to take the amulet and then engages in a feral swordfight with Justin, freely admitting his part in trying to stop the plan.
Voice Acting Around Trademarks: Late in production, concerns arose that the name "Frisby" would land them in legal trouble with the makers of the Frisbee toy. Many of the voice actors returned to the studio for additional ADR work in order to replace every instance of the name "Frisby" in the film with "Brisby". Only Elizabeth Hartman and John Carradine—the actors for said character and the Great Owl—could not, so their lines were mechanically edited.
Would Hit a Girl: Near the end, Jenner smacks Mrs. Brisby out of the way when she tries to warn the rats that NIMH is coming.
You Dirty Rat: Averted for the most part. The rats even gain a sense of morality and even consider it wrong to steal from humans, the very species who locked them up and experimented on them. However, this trope is played frighteningly straight with Jenner.
The Secret of NIMH 2: Timmy to the Rescue has examples of the following tropes:
Action Girl: Jenny, who is arguably more responsible in stopping Evil!Martin 's plans than Timmy. She does get a few odd Distressed Damsel moments however.
They say no because they believe the mission could be a risk to Thorn Valley's location (especially since scientists from NIMH are apparently searching for their lost experimental animals at the beginning of the film). It doesn't quite befit their actions elsewhere in the movie however, since they entrust several other people (including Jeremy of all people) with it's location without holding them captive.
Ascended Extra: Though Timmy was a large plot point of the original movie, the character itself had little of a role or spotlight. In the sequel he is in the starring role. This role promotion is identical to that of the book's sequels.
Anthropomorphic Shift: Especially jarring since they show clips from the original movie at the beginning.
Dreadful Musician: Not many of the people who have their own musical numbers in this movie can actually sing.
Eric Idle and Dom De Luise as usual kind of skirt around this, but their tendency to do so deliberately for laughs (in addition to the overwhelming Narm Charm in Idle's number) more than makes up for it.
Dude, Where's My Respect?: Mrs Brisby. The rats worship her husband for helping them but seemed to forgot that she warned them to move to Thorn Valley to escape from NIMH in the first movie. She doesn't even get a statue. For that matter neither does Nicodemus, who they seem to almost worship now.
Jenny also was equally responsible for saving Thorn Valley than the prophesised Timmy as well. She escaped NIMH alone, she went on a dangerous journey to Thorn Valley alone, and she was willing to go back and defeat the villains alone. She braved much greater dangers than Timmy, and later is, in fact, directly responsible for stopping the bad guy!
Evil Brit: When Martin becomes evil in the sequel, he inexplicably gains a British accent.
And later he loses it when he becomes good again, and he reverts back to his young age without explanation!
Evil Is Hammy: Arguably one of the better parts is Evil Martin's dramatically hammy performance in the later portion of the film performed by Eric Idle, who seems to have loads of fun delivering every last line. He doesn't just chew the scenary as Evil Martin, he gobbles it up whole, shats it back out, and then gobbles it up again, rinse and repeat twice more. ("You'll be happy. Oh, so happy, if youjust SAY YYYYYYYYEEEEEEESSSSSSSS!!!!!")
Half-Dressed Cartoon Animal: Everyone, even the previous exceptions from the previous film (eg. both Mrs Brisby and Aunt Shrew wear large gowns).
The sequel makes a strange joke about the rats wearing underwear, but the characters are clearly still not wearing pants.
Laughably Evil: Evil!Martin is a sadistic maniac who desires to have the whole of Thorn Valley destroyed For the Evulz. On the other hand he is also a Large Ham of the highest order and offers some of the funniest dialogue in the movie. Being voiced by Eric Idle helps as well.
Off Model: Most of the film has standard but relatively consistent animation throughout most of the movie, but then the animation gets kind of sloppy when it comes to Evil!Martin, with his facial structure (especially his nose, going from mouse-shaped to a more elongated rat-like shape in some expressions) changing a lot during his scenes.
Although the film makes the poor decision to include some footage from the first film as an introduction; the reason this is a poor decision is both because the sequel has very little to do with the original, save the names of the characters, but mainly because the first film was animated by Don Bluth's studios. The sequel was not.
Role Reprisal: Dom Deluise and Arthur Malet both reprise their roles as Jeremy the Crow and Mr Ages.
Save the Villain: Well, the villain is Timmy's brother, Martin, so he had a good excuse to save him.
Selective Enforcement: The rats are very protective of Thorn's Valley's secrecy, even borderline holding residents hostage to avoid risk, this is despite the fact characters such as Jeremy were shown freely entering and leaving it prior.
Self-Fulfilling Prophecy: Had Timmy not been sent away to Thorn Valley, a large part of the film would never have happened. In fact, any of the Brisby children could have gone instead of Timmy and the film's plot would have been exactly the same. You can even go so far to say that if Timmy hadn't been prophesised to be a great hero, then Martin wouldn't have run off to prove that he could have been the hero, getting himself kidnapped & becoming Brainwashed and Crazy.
Sissy Villain: Doctor Valentine in the sequel. Might as well call him "the camp evil scientist that wears eye liner" (seriously).
It also doesn't help much that on top of being nonexistent in the original film and having no speaking lines whatsoever, Jenny still builds him up to be an absolutely depraved villain hellbent on the capture and destruction of the rats, only for him to finally emerge at the climax as nothing more than Evil!Martin's mindless pet. Literally.
We Can Rule Together: Evil!Martin to Timmy, with the added bonus of some sort of implied lobotomy so Timmy will be just as evil and oh so happy as him.
"Well Done, Son!" Guy: "So, Timmy, your dad was practically a living god. We just can't stop praising him and, since some random prophecy said you were going to be the hero of this movie, we WILL make you be just like him. No complaints. Questions?"