A neighbor visits her friend, taking with her her child, a little girl about the same age as the friend's little girl. Both children being full of mischief, they immediately put into execution a number of startling and ingenious pranks. While the laundry maid is entertaining her policeman lover, the children pin the policeman's coat tail to a sheet which is being ironed by the laundry maid. They next get a trap containing some mice and let them loose in the parlor where their parents are entertaining guests at a card party. They put the cat in the piano, make finger marks with flour on the hack of father's coat, causing his wife to think he has been embraced by the cook; they find grandfather asleep, his slippers lying on the floor, and nail the slippers down, and grandpa upon awakening receives a severe fall.