One day, Rabbit is admiring himself in a mirror when Tigger bounces in on him and accidentally breaks the mirror. Rabbit tells Tigger that he'll have seven years bad luck. At first Tigger is horrified, but quickly scoffs at the idea, and states that Rabbit will have the bad luck because it's his mirror - now it's Rabbit's turn to be horrified Tigger swears to protect him from the bad luck, however that turns into a disaster. Rabbit remembers that it is in fact Pooh's mirror and Pooh will have the bad luck - however Tigger wants to help. He has Pooh and Piglet swap clothes, to confuse the bad luck, but both of them receive bad luck.
Tigger conceals Piglet in a "safety" shelter for seven years so his bad luck won't hurt him or anyone else. However, as he and the others leave, lightning strikes the shelter almost immediately (thanks to a lightning rod Tigger foolishly placed on the top), leaving poor terrified little Piglet in a whimpering and gibbering mess. The gang is forced to carry Piglet's bed with them.
Rabbit discovers that it's Tigger's bad luck that's following everyone around. Tigger realized he's right and sadly leaves the 100 Acre Wood. The Gang look for him at night and want him to come back because they miss him and reverse his bad luck by "fixing" the mirror (taping a crude drawing of Tigger onto the mirror so that he thinks it's his reflection). Tigger bounces with glee, relieved that his bad luck is finally over just as Piglet finally snaps out of his trauma, having no idea what's going on.
Atop the hill near the big tree, Christopher Robin tells Pooh that breaking a mirror is a silly superstition. Pooh said he knew, but was only playing along so that bad luck wouldn't feel left out. He fishes around in a bed of clover and finds a four leaf one... Just in case.