Nit-Witty Kitty.Tom is chasing Jerry around Mammy Two Shoes, while she is screaming out confusing instructions on where to chase Jerry. She has a broom ready to hit Jerry but instead she clumsily hits Tom. This hit to the head causes Tom to forget who he is and he believes he is a mouse. Mammy asks Tom if he is okay but he starts to squeak she becomes scared and jumps onto a kitchen chair for protection. Tom terrorises Mammy by shaking the chair causing her to fall off it, then quickly flees from the deranged cat. Tom then heads over to the refrigerator and grabs a piece of cheese, before entering Jerry's mouse hole. Tom then moves into Jerry's small bed causing it to break underneath him. Jerry gets angry and exasperated having to share with an oversized 'mouse'. Jerry then overhears Mammy on the phone talking to the doctor about Tom. He hears that Tom is suffering from amnesia. Seeing Tom approaching her with mischief on his mind, Mammy cuts her phone conversation short and attempts to evade him by walking away on stilts. Tom pulls the stilts from under her causing Mammy to fall and he runs back into the mouse hole.