10 Best South Park Celebrity Cameos
5. Jennifer Aniston
Though it was far from South Park's first celebrity voice cameo, this is one that stands out more than most.
Jennifer Aniston was at the height of her Friends fame when she bounced over to South Park for what was - in contrast to most entries on this list - a pretty substantial role in the episode.
That episode was the 1999 installment, "Rainforest Shmainforest", which saw Aniston voicing Ms. Stevens, the head of an environmentalist choir tour called "Getting Gay With Kids". The boys are forced to join the tour, and Kenny falls in love with Kelly, a choir girl prone to aggressively picking her nose and calling him every "-nny" name but his own.
As Kenny falls in love with Kelly, Ms. Stevens gradually falls out of love with the rainforest and her mission to protect it. Though she started out as earnest in her idealism, she ends the episode exhausted, fed up, and disenchanted. Aniston absolutely sells it, too.
She literally goes from, "The rainforest is very fragile. We must take only pictures and leave only footprints," to, "I hate the rainforest! You go right ahead and plow down this whole f**king thing!" Those are direct quotes.