The Mouse is a fictional character in Lewis Carroll's 1865 novel Alice's Adventures in Wonderland. He appears in Chapter II "The Pool of Tears" http://www.gutenberg.org/files/19033/19033-h/19033-h.htm#II_THE_POOL_OF_TEARS and Chapter III "A Caucus-Race and a Long Tale" http://www.gutenberg.org/files/19033/19033-h/19033-h.htm#III_A_CAUCUS-RACE_AND_A_LONG_TALE.
Alice, the eponymous heroine in the book, first talks to the mouse when she is floating in a pool of her own tears, having shrunk in size:
With no response from the mouse, Alice fears that it may not speak English and attempts to speak French. Upon mentioning the French word for cat, chatte, the mouse panics. This leads to a discussion about cats and dogs, culminating in the mouse telling Alice his history.
When Alice hears the mouse's "long and sad tale", she is watching his tail. So, she imagines the tale in its shape. The "Fury" referenced in the tale is Carroll's childhood friend's dog.
<pre> Fury said to a mouse, That he met in the house, "Let us both go to law: I will prosecute YOU. --Come, I'll take no denial; We must have a trial: For really this morning I've nothing to do." Said the mouse to the cur, "Such a trial, dear Sir, With no jury or judge, would be wasting our breath." "I'll be judge, I'll be jury," Said cunning old Fury: "I'll try the whole cause, and condemn you to death."'</pre>
Although the Mouse does not appear in the 1951 Disney film, part of his personality has been integrated to the Dormouse.
The character makes an appearance in the 1985 made-for-TV adaptation of Alice in Wonderland and is portrayed by Sherman Hemsley. In this incarnation the Mouse sings "I Hate Dogs and Cats" before joining in the Caucus-race with the rest of the animals that have been floating on Alice's pool of tears.
In the 1983 anime Fushigi no Kuni no Alice, The Mouse appears in overalls. Though he dislikes cats, he isn't actually scared of them.
In Jan à  vankmajer's 1988 film adaptation, The Mouse swims up to Alice and climbs atop her head. Seemingly unaware that Alice is alive, he sets up camp, driving stakes into Alice's head to support his cooking pot. Alice tolerates this, but when the Mouse sets a fire to begin cooking, Alice proclaims he has gone "too far" and submerges her head under the water, to the Mouse's surprise and dismay.
In the anime and manga series Pandora Hearts The Mouse is reimagined as Gilbert Nightray with his fear of cats and his younger brother Vincent is based on the Dormouse.
The character also makes an appearance as Mr. Mouse in the 1999 made-for-TV Hallmark adaption and is portrayed by Ken Dodd.
In the 2025 Russian musical film Alice in Wonderland, the Mouse is female and is portrayed by Polina Guchman.