After soccer practice, Bart waits patiently to be picked up by Homer. And waits and waits, as Homer has forgotten about it and pays no attention to Marge's reminder. When he finally remembers, hours have passed, it's long since started raining, and Bart is bitterly awaiting him at the field.
Homer thinks the whole matter should be brushed off ("We could argue about who forgot to pick up who until the cows come home"), but this only makes Bart madder. When he sees a commercial for the Bigger Brothers organization on TV, which matches adult mentors to kids who need them, he calls it up and tells them that he doesn't have a father...
Behind his family's back, Bart starts spending happy days with Tom (voiced by Phil Hartman), a good-natured guy who believes Bart's sob story of Parental Abandonment
. Homer eventually finds out Bart's secret, and when a confrontation culminates in Bart admitting he prefers Tom's company, Homer sets out for revenge...by becoming a Bigger Brother himself.
Homer is matched with Pepi, a street urchin who is grateful for Homer's attention. But he decides to take him on an outing to the Seaquarium at the same time that Bart and Tom are there. Tom is not happy to see the man who "abandoned" Bart, and the adults wind up brawling; eventually the police break up the fight. With the truth about Homer in the open, Tom decides to become Pepi's new Bigger Brother while Homer and Bart reconcile over how surprisingly capable Homer was in the brawl.
In the B-plot, Marge discovers that Lisa has become addicted to the expensive 1-900-number "Corey Hotline" (enjoy a different message each day from Teen Idol
Corey!) and eventually forces her to go cold turkey by challenging her to go one night without calling it. Lisa does pick up the phone by night's end...but goes no further than the time-and-temperature number, and Marge is satisfied to see her daughter's willpower.
"Brother from the Same Planet" contains examples of:
- Body Horror: Bart's Imagine Spot of Homer's face melting.
- I Have No Son: Inverted. Bart calls the Bigger Brother program and says he doesn't have a father, then poses as an orphaned street rat whose father abandoned him.
- Imagine Spot: "Now how 'bout a hug?"
- Also Homer has one in which he finally goes to pick up Bart from soccer practice, only to find a spiky-headed skeleton.
- Never Trust a Trailer: Original promos for this episode suggested this was a going to be a serious, dramatic episode, with Bart saying "Tom's a better father than you ever were!", followed by a shot of Homer crying. In the actual episode, Homer was crying after confessing that he fell for a record and tape club scam that promises the first couple albums for a penny before jacking up the prices.
- Shout Out
- Milhouse writes "Trab Pu Kcip" on a mirror when Bart tries to psychically project a message to Homer.
- Homer compares a Dumpster-dwelling hobo to Oscar the Grouch.
- Take That: Bart watches Krusty guest-hosting an episode of Tuesday Night Live, which is so bad that Bart remembers the days when Joe Piscopo was on the show. At the time, most critics were claiming that Saturday Night Live was going into another period of Seasonal Rot due to bad host choices and thin sketches with one-note characters (though complaints about SNL's quality have been hovering around the show since the first time people thought SNL was going downhill — which would be when Chevy Chase left the cast in 1976). The writers on the DVD commentary claimed that this was more of a backhanded Affectionate Parody, as most of The Simpsons writers on the show at the time got their start on SNL and left because they pretty much used their time on the show for extra money and a stepping stone for bigger and better projects.
- Unintentional Period Piece: By the Turn of the Millennium, 1-900-numbers fell out of fashion, so this episode's B-plot may seem alien to those who didn't grow up in The Eighties and The Nineties.
- What Could Have Been: Tom Cruise was supposed to play Tom.