Children entering Toontown these days may need to be accompanied by an adult.

Visitors to the seedy side of the burgeoning burg easily could bump into Frank Murphy spewing language on "F Is for Family" that would make Archie Bunker blush, BoJack Horseman choking his girlfriend or "South Park" bad boy Eric Cartman pretending to be disabled to compete in the Special Olympics.

These colorful, often off-color, residents have been instrumental in making this the most daring, and delicious, period of TV animation. Just don't let them anywhere near your kids. (See our 10 picks for best adult cartoons here.)

"I have definitely heard people tell me their 12-year-olds watch 'Archer,' and I'm like, 'Oooh, that's too young for me,' " said Casey Willis, an executive producer for that long-running FXX comedy, which features a narcissistic secret agent who carries as many condoms as he does bullets. The spy sendup is one of more than a dozen animated series in production that carries a TV-MA rating, which means it's designated for mature audiences only.

"I don't want to limit our audience," Willis said. "But I think our viewers should at least be in high school."

Audrey Diehl may be the vice president of animated series at Warner Bros., but even her household can fall into the trap of thinking all cartoons are safe for youngsters.

"My husband doesn't really know animation, so he'll sometimes pull something up and start showing it to my kids, and I'm like, 'No, no, no, no!' " said Diehl, who spent 14 years at Nickelodeon. "I think it's going to be part of a whole new education for consumers to help them understand that just because something is cute and colorful, it doesn't mean it's for kids."

For decades, grown-up cartoons were restricted to the big screen.

Jazz Age flapper Betty Boop, one of the most popular sex symbols of the 1930s, may not have been bad, but she was certainly drawn that way. The 1972 film "Fritz the Cat," featuring a hedonistic gray tabby, got slapped with an X rating.

The first animated sinners in prime-time television were Barney Rubble and Fred Flintstone, who puffed cigarettes in commercials during their initial six-year run in the 1960s.

Then came "The Simpsons." In an early episode from the 1989 premiere season, the family takes unbridled joy at giving one another electric shocks during a therapy session.

"I was in elementary school when the show first came out, and it blew my mind," said Phil Lord, who helped create the Academy Award-winning 2018 film "Spider-Man: Into the Spider-Verse," and is an executive producer on the new Fox cartoon "Bless the Harts," best described as "King of Hill" from a female point of view. "It sent me to animation festivals just to see the breadth of the art form and what it can do."

But Homer's hijinks would be child's play compared with the shows that would follow.

The '90s would bring us "Beavis and Butt-Head," "Spawn," "South Park" and "Family Guy," all series where you'd think twice about hiring any of the characters as your babysitter.

Matt Brady, a pop-culture expert based in North Carolina, thinks "Batman: The Animated Series" and its "Superman" spinoff, both of which launched in that same decade, were particularly influential in setting a darker, deeper tone. He still gets goose bumps thinking about the episode in which police officer Dan Turpin was killed after saving the Man of Steel.

Brady is betting that today's animators were equally moved when they were growing up — and it's showing up in their work.

"I think we're seeing the effects of nerds being in power," said Brady, who recently put out the book "The Science of Rick and Morty," a deep dive into the cult hit that once featured a sexual predator named King Jellybean. "It's a whole generation who want to create stuff as fun and edgy as what they loved as kids."

Drawing outside the lines

Modern TV cartoons can pretty much go wherever they want — although Willis admits network execs once nixed a scene in which Sterling Archer distracted a villain by tossing a baby in the air.

"In animation, you can watch people experience torture and evisceration with blood gushing. If you saw that in live action, it would be horrible," said Margaret Dean, head of studio for Crunchyroll, a San Francisco-based company that specializes in streaming animé. She also is president of the advocacy group Women in Animation. "The nature of animation allows us a degree of separation from what's real. There's just something about that one step of removal that makes it funny."

Brooklyn Park writer Michael Starrbury reveled in the freedom while developing "Legends of Chamberlain Heights," the short-lived Comedy Central series that came across like a more vulgar version of "Fat Albert and the Cosby Kids."

"We are able to get away with things you couldn't in live action," said Starrbury, who was nominated for an Emmy for his work on the Netflix miniseries "When They See Us." "Characters can be a little more raunchy. They can be more racy and salacious." He ultimately soured on the show because his partners didn't want to be as satirical or political as he would have liked.

He may have felt more at home in the writers room for a number of current hits that thrive on tackling squirmy subjects.

The characters in "Big Mouth" confront the horrors of puberty. The heroine of the fairy-tale spoof "Disenchantment" has more problems battling sexism than dragons. "South Park" has been tackling subjects such as sexual harassment, opioid abuse and hate crimes for more than two decades.

During last Sunday's Emmy awards, "Family Guy" patriarch Peter Griffin suggested that the ceremonies were all about discovering the next Bill Cosby or Roseanne, a joke that would have been much more risqué if attempted by Seth Meyers.

"Animation has the ability to tell stories, tell jokes and make commentary on subjects and characters that live action doesn't," said Craig Erwich, senior vice president of originals for Hulu, which features "South Park" repeats in its vast animation library. The streaming service will premiere a series next year called "Solar Opposites," in which Minnesota-based comic Mary Mack plays a member of a family of aliens forced to live in middle America.

"It's a massively popular content category on Hulu across many different age groups, many different mind-sets and many different sensibilities," Erwich said. "That's why you're seeing so much of it, not just on Hulu, but in the industry."

Family ties

Not all grown-up cartoons are taboo to toddlers. Youngsters may not catch the digs at ESPN's Stephen A. Smith and privatizing prisons in Sunday's 31st season premiere of "The Simpsons," but they'll at least snicker at the tater-tot fight in the school cafeteria.

"Final Space" creator Olan Rogers aims his TBS sci-fi spoof at adults, but he doesn't want to alienate everyone else.

"It's good to have a specific target, but it's a pretty big dartboard, you know?" he said. "You can't just go for a pinpoint spot. You'd be excluding too many people."

Ike Barinholtz, who voices a character on "Bless the Harts," said prime-time cartoons are now one of the few genres a family can enjoy together. "We didn't have that when I was younger," he said. "I never said to my parents, 'Do you want to watch "Snorks" with me?' "

And then there are the shows kids shouldn't be watching — but do anyway.

Brady was explaining the TV-MA-rated "Rick and Morty" to some friends at a recent party when he noticed a couple's teenage boys leaning into the conversation.

"They weren't taking part, because it might have revealed too much," Brady said. "It's forbidden fruit. It's not made for kids — and that's why it's so popular with kids."