The Caves are underground caves in Arlen where, according to Peggy, half of Arlen's unplanned pregnancies take place. Hank states that The Boneyard section of The Caves are where most people have gotten to second base. It is also, according to Hank, where teenagers go to make "whoopee."
The Caves appear, and are only mentioned, in The Son That Got Away.
When Bobby and Connie continually fool around during class, their music teacher Eugene Grandy, loses patience with them, explaining to them that it's time to involve their parents due to their misbehavior. Hank and Kahn show up at Tom Landry Middle School, and Eugene Grandy informs them of Bobby and Connie's goofing around during class. Hank and Kahn proceed to punish their children. Bobby's punishment is to clean Hank's rain gutters, and Connie's punishment is to mow the lawn. Hank, flabbergasted, tells Kahn that mowing the lawn is a privilege, not a punishment.
When Bobby grows weary of cleaning the rain gutters, he heads over to Connie's house, who's taking a break from mowing the lawn. Upset with how their parents treat them, Bobby and Connie decide to do something fun, and hop on a bike together. Bobby, much to the dismay of Connie, stops by Joseph's house, inviting himself along. While deciding where to go for fun, Joseph recommends that they go to The Caves.
Bobby, Connie and Joseph, having decided to explore The Caves, ride their bikes to the Get In Get Out. While there, they purchase some supplies before their journey to the caves. Joseph purchases tube chips and spray cheese, Bobby purchases glow wands and pantyhose for Connie, and Connie purchases a pack of scented candles.
When Hank and Kahn realize their kids have run off, they become angry, and begin driving around Arlen searching for them. Dale begins to worry when he wonders where Joseph is, relying on him to bring back lottery tickets. Meanwhile, Bobby, Connie and Joseph continue on their journey, making there way across a field, and through some tall weeds to the entrance of the cave. As they make their way into the dark cave, Randy, who's flying his remote control plane nearby, warns them against going in. Joseph and Connie disregard Randy's warnings, and continue on their way. Bobby, however, becomes frightened as he makes his way in to the darkening cave, suggesting that perhaps they should heed Randy's warnings. As they're crawling into The Cave, Randy, who's watching them from the entrance of The Cave, gives one last warning before getting hit in the head by his plane and knocked over, having not paid attention the plane flying above him.
As they venture deeper into the cave, using the scented candles as light sources, Bobby stumbles, struggling to climb a steep slope. Bobby states that he doesn't think he can make it, and Joseph, taking off his shirt, tells Bobby to grab on to it, and pull him to the top. Once at the top, sitting on an old mattress, they shine the scented candles against the wall, revealing old graffiti that reads "The Boneyard." Joseph cheerfully explains that they've made it to The Boneyard and they all high five. Connie explores the area with her candle, revealing some more graffiti that reads "Seniors '76" and "Frampton Comes Alive!" Joseph finds an old Playboy magazine, and begins reading an article from it. Finding it silly, Joseph and Connie start laughing, resulting in a closer bond, and Bobby feeling left out.
Hank, Kahn and Dale search frantically around Arlen together in Kahn's minivan for Bobby, Connie and Joseph. Hank recommends searching for them at Hobby Oddyssey, and Kahn recommends they look for them at a sheet music store. Eventually, they make their way to the Mega Lo Land section of the Mega Lo Mart, and search there with no success. Upon leaving Mego Lo Land, Hank notices Eustice and his son Randy leaving the Mego Lo Care section of the Mego Lo Mart. (Randy received treated inside for his head injury from earlier) Hank asks Randy if he has seen Bobby, Joseph and Connie. Randy tells Hank that they're in The Caves, much to the horror of Hank and Dale. In a panic, Hank, Kahn and Dale rush across the Mega Lo Mart parking lot, racing back to Kahn's minivan. Kahn, curious as to why Hank and Dale aren't relieved to learn where their kids are, learns from Hank, much to his dismay, that The Caves are where teenagers go to make "whoopee."
Back at The Caves, Joseph finds a women's bra, and offers it to Connie. Bobby, noticing the bond between Connie and Joseph grow stronger, feels increasingly left out, and in a desperate attempt to obtain affection from Connie, picks up a tin of chewing tobacco off the ground, and offers it to her. Suddenly, the last of The Scented candles burns out, leaving Bobby, Connie and Joseph in thick darkness. Bobby, Connie and Joseph become frightened in the darkness. Bobby, using some quick thinking, pulls out one of the glow wands he purchased at the Get In Get Out. As the light from the glow wand fills The Cave, Bobby, much to his dismay, sees that Connie and Joseph have been holding hands in the dark.
Hank, Kahn and Dale pull up to the entrance of The Cave, coming to an abrupt halt in Kahn's minivan. While they quickly hurry inside, Hank recommends to Dale that he go tell Peggy and Mihn where they are, so they don't worry. While Joseph and Connie decide that they should be on their way, they realize that they're lost, unsure which way they came and where to go, as there are many different caves. Joseph and Connie, frightened, hug each other in comfort, while Bobby, becoming worried, begins to impulsively eat the snacks he purchased at the Get In Get Out. While Hank and Kahn struggle to find The Boneyard in The Cave, Joseph and Connie become upset with Bobby for eating all the food. As Bobby, Joseph and Connie begin to lose hope, Bobby, feeling all alone, explains to Connie and Joseph that when they time comes, he wants them to eat him. Connie, touched by this, thanks Bobby, telling him that he's brave and kind for offering himself. While Hank and Kahn are making their way through the narrow caves, they stumble and drop into a big pile of beer cans. Hank and Kahn realize that they themselves are lost, and wait in hopes of Dale bringing The Fire Department. Hank, explaining that many in Arlen have got to second base at The Boneyard, grows concerned. Eventually, Hank and Kahn begin reminiscing and bonding together. Hank and Kahn end up laughing so loudly, that Bobby, Joseph and Connie hear them from The Boneyard in the distance and decide to investigate, following their laughter in one of the surrounding caves. Bobby, Connie and Joseph, glow wands in hand, make their way through the cave and stumble down into the same big pile of beer cans. Hank and Kahn, happy and relived, hug their kids, and greet Joseph. While awaiting rescue, Bobby notices a hole above them, and to the surprise of Hank, Boomhauer proceeds to calls down to them, shouting from above. Shortly after, They're rescued by The Arlen Fire Department and airlifted out of the hole. Upon rescue, they're all reunited with their families waiting who're eagerly awaiting their safe return.