While the Griffins are housebound during a hurricane, Brian ingests psychedelic mushrooms. He sees bizarre and unsettling things, and acts accordingly. Meanwhile, the rest of the family is bored and irritable, and Meg finally lashes out at Chris, Lois and Peter for all the crap they've given her.
The crossover starts on The Cleveland Show S03E02 The Hurricane (I). It continues on American Dad! S08E02 Hurricane! (III).