My Grandson, Myself

"Willow: Wow! Like father like son. Oz: How 'bout exact same guy like exact same guy."

- Buffy the Vampire Slayer, "Enemies"

You're immortal, or just extremely long lived, and you want to stay in one place for a long time without people noticing that you don't age. So what do you do? You reintroduce yourself as your own son, then grandson, etc. This handily gets around the problem of having to explain how you could have served in WWII and still only be 25 years old.

Bonus points if you keep the same name - so John Smith becomes John Smith Jr, becomes John Smith III, etc. Bonus idiocy-points if you've ever allowed someone to paint your portrait or take your photograph while pursuing this strategy, as it will be discovered and expose your deception in future decades.

A special case of Identical Grandson where they are actually the same character. Not to be confused with My Own Grampa.

The inversion (a character claiming to be immortal is actually an identity passed down from father to son) is Legacy Immortality.

Anime and Manga
""If it's just giving a temporary introduction to ordinary people, then there is no problem. But you will use your real name when conversing with fellow immortals, and your body will reject establishing a false identity in this world""
 * Ernst von Boem in RahXephon.
 * Rin from Mnemosyne uses this during a visit to an old acquaintance from WWII when the latter recognizes her.
 * Neo Angelique has, who reveals to an old friend that he is in fact in old friend instead of the grandson of his friend.
 * Suberted in Baccano!!—as part of the original 1711 contract, all immortals are rendered incapable of establishing long-term false identities, which means all of them will eventually have to give that awkward explanation as to why their passport claims they're six or seven times older than they look.
 * While immortals must reveal their true identity in the presence of another immortal, there is nothing that states they can't create false identities around mortals.
 * According to  in the prologue of The Rolling Bootlegs, there's a mental block against setting false IDs:


 * Fullmetal Alchemist: Pride, aka, does a variation in that he's pretended to be What better way to innocuously keep tabs on what the government is doing?

Comic Books

 * Vandal Savage in The DCU.
 * Lex Luthor, dying from radiation poisoning ('cause it turned out kryptonite was just like any other radioactive substance to humans), faked his death by plane crash then had his brain transferred to a clone body, introducing himself to the world as his own son. After the reveal (which involved clone degeneration and him levelling Metropolis), he pulled a Karma Houdini by selling his soul for a cure and then blaming everything on an insane clone that faked his death and took his place.
 * Hob Gadling/Sir Robert Gadling/Bobby Gadling in The Sandman mentions he has done this several times.
 * The Hobs Leviathan chapter implies that this is a fairly common practice among immortals in the Sandman mythos
 * Also inverted in the DC/Marvel All Access crossover series. That old drifter who started helping Axel with his powers? Not so much.
 * Milestone Comics Icon series. The title character started off as "Augustus Freeman" in Civil-War-Era America and made a habit of this sort of identity change. By the time the comic started in the late 20th century, he was Augustus Freeman IV.
 * Hawkman started doing this after the Golden Age Hawkman from the 1940's was retconned into being the same character as the currently active Hawkman.
 * In The League of Extraordinary Gentlemen, Mina Harker and Allan Quartermain drink from the Fountain of Youth, restoring both to their late-20's selves. Mina lives on as herself and is noted to be "remarkably well-preserved," while Allan invokes this trope and poses as "Allan Quartermain Jr."
 * Many of the Destines from ClanDestine have done this. In the first volume, Kay has to establish her new host body as the daughter of the same name as her old one- somewhat complicated by the fact that she hadn't planned on the switch and therefore never mentioned having a daughter. The sequel miniseries establishes that Walter has also been repeatedly posing as his own son (under the same name), and a villain discovers that the family has a suspicious pattern of births and deaths in out of the way locales with conveniently poor documentation.

Fan Works

 * Undocumented Features: In the wake of a sorcerous rewind of her physical age during the events of the Ragnarok, Captain Sarah Inazuma of the Phoenix Queen -- better known to some as Azula, former princess of the Fire Kingdom, Dìqiú -- is forced to take on the persona of her identically-named late-adolescent daughter, to whom she has left all her worldly goods.

Film

 * The Haunted Mansion has Master Gracey who poses as his own grandson.
 * John in Man From Earth claims that he has passed himself off as his own son multiple times.
 * In Dracula 2000, Dr. Abraham Van Helsing uses Dracula's blood to keep himself immortal, in order to continue research on how to kill the vampire king for good. In the modern day, he passes himself as his grandson, "Matthew Van Helsing".

Literature

 * The Misenchanted Sword by Lawrence Watt-Evans gives the main character immortality. Once he solves the problems with it, he does just this by telling all his friends he's leaving his business to a long-lost relative. Then he gets himself youthened and comes back as the relative.
 * in the Discworld novel Pyramids is an interesting case of this: not only has he been, he has always been that way (or at least for untold tens of thousands of years) as a result of . As far as we know, he never actually pretends to be his own descendant - people just assume.
 * It's more a matter of people trying very hard not to think about it too much, as being fed to crocodiles often offends.
 * Lazarus Long mentions doing this in Robert A. Heinlein's Time Enough for Love. Since he effectively doesn't age, he uses makeup to make himself slowly look older over time. After he's been in an area for long enough, he comes back without the makeup as his "son."
 * A minor but long-lived villain in H.P. Lovecraft's The Case of Charles Dexter Ward, a sorcerer named Simon, writes a letter to the main villain, explaining a Chekhov's Gun detail (Simon's disappearance) that's dropped fairly early on: "In this Community a Man may not live too long, and you knowe my Plan by which I came back as my Son."
 * In the Belgariad, Tolnedrans don't believe in Belgarath and Polgara's immortality, and think it's actually a dynasty of sorts.
 * Inverted in Jasper Fforde's The Eyre Affair. Thursday meets a member of the Chronoguard, the time-traveling police, who introduces himself as the grandfather of an ex-boyfriend of hers. However, after the man dies, Thursday learns that the man actually was her ex-boyfriend, who due to an accident in the timestream had been aged over sixty years. Not bearing that Thursday should meet him like that, he took on a false identity.
 * In Poul Anderson's The Boat of a Million Years several characters do this.
 * Tuck Everlasting
 * In the third book of The Pendragon Adventure, Bobby claims to be his own grandson when.
 * In Barry Hughart's Bridge of Birds,.
 * In the Deverry novels, Nevyn was a close adviser to the first King in Cerrmorr and the last King in Cerrrmor over the course of a century long civil war. When his second King's wife remarks on the coincidence of his name (Nevyn is not a common name, as it means No One), Nevyn claims that the Nevyn who served as adviser to Glyn I was his grandfather. Of course, Neyvn made a point of spending the decades between the death of Glyn I and the crowning of Maryn I a long way away from Cerrmor, to keep people from realizing that he didn't age.
 * In the short story "Bargain with the Wind" by Sharon Shinn, narrator and Old Retainer Nettie is revealed at the end to be an earth spirit whose job is to serve the masters of the house. When a new family moves in and offers to let her retire, she suggest as her replacement her "niece", Norah, and then changes her form to that of a young girl so she can continue to serve the new owners.
 * The main character in Saturn's Race by Larry Niven's and Steven Barnes undergoes a top secret rejuvenation process, and ends up assuming the identity of a grandson.
 * Short-term variant: In Bloodlist, Jack Fleming rises as a vampire looking a decade younger than his real age, so poses as his own near-identical younger brother while pursuing the gangsters who murdered him.

Live-Action TV

 * Captain Jack Harkness in the Torchwood episode "Small Worlds."
 * Mayor Wilkins III (aka Mayor Wilkins I and II) in Buffy the Vampire Slayer.
 * In the Charmed episode "Saving Private Leo," Leo Wyatt poses as his own grandson to attend a 60th-anniversary reunion of World War II veterans.
 * The Trill ambassador in Star Trek: The Next Generation poses as his own son to avoid letting the Federation know that the Trill are a race of (benign, symbiotic) Puppeteer Parasites.
 * The Doctor in the Doctor Who Expanded Universe is occasionally referenced as doing this so he can continually visit places he likes. Of course, he has the advantage that he doesn't look the same every time.
 * Duncan MacLeod from Highlander the Series sometimes has to resort to doing this when mortals from his past think they recognize him - naturally they tend to suggest this themselves once they get over the stunning likeness.
 * MacLeod also at one point claims to be his own grandson to access a bank account he'd set up in the previous century. Naturally, he had collected quite a bit of interest over the years.
 * The original movie has what could be the page quote: "So what we're dealing with here is a guy who's been around since at least the year 1585, pretending to cark it every once in a while, then leaving all his money to some kid who's been a corpse for decades and taking their identity."
 * Subverted in the Supernatural episode "Everybody Loves a Clown": Dean and Sam think the circus leader may be a Rakshasa because he looks just like a picture of his father. As it turns out, it wasn't him.
 * A variant is used in Ultraviolet, where the death of a real grandson allows a code 5 to re-enter society using the deceased's identity.
 * In one of the canonical Heroes graphic novels, Adam Monroe, an immortal man who's nearly 400 years old, states that during one of his innumerable marriages, he and his wife, to hide the fact that he's staying the same age and she's aging normally, first introduce him as her husband, then eventually their son, then grandson.
 * An episode of The Twilight Zone had a woman who did this, and claimed that the old woman living with her was her grandmother when it was really her daughter..
 * Stefan and Damon Salvatore of The Vampire Diaries pretend to be descendants of "the original Salvatore brothers" from Mystic Falls' founding families. However, when Elena discovers that both Stefan Salvatores are identical, she realizes the truth.

Theatre

 * Played with in Sunday in The Park With George: although late 20th-century artist George is actually a different person from late 19th-century artist Georges Seurat, the Mind Screw-y final scene has him effectively turn into the famous painter, as he reconciles with his estranged mistress, Dot (who is actually his great-grandmother) from beyond the grave.

Tabletop Games

 * GURPS 4e has this among Baron Janos Telkozep, an iconic vampire character.
 * King Kaius III in the Eberron campaign setting is really his great-grandfather (and secret vampire) King Kaius I. Kaius II (and the real Kaius III) were really themselves, and it's strongly hinted that the latter has been locked up somewhere.
 * Khelben "Blackstaff" Arunsun the Elder in the Forgotten Realms campaign setting, who took on the identity of his actual grandson Khelben "Ravencloak" Arunsun the Younger.
 * Strahd von Zarovich, the Ravenloft setting's most infamous vampire, has been pulling off this gambit for the past eleven generations, feigning his own death and leaving rulership of Barovia to his identical "son".
 * Itohiro Nakami in Dark?Matter setting of Alternity/D20 Modern. He pretends to be his own son to transfer the leadership position of Hoffman Institute without becoming suspicious, being a Grey / Fraal and all that who uses illusions to appear as a human.

Video Games

 * In The Elder Scrolls IV: Oblivion, does this as.
 * In Shadow of Destiny, it is implied that.

Web Comics

 * Magellan has the case of elderly superhero pulling this after.

Western Animation

 * In the 2003 series Teenage Mutant Ninja Turtles, the Utrom Shredder pretends to be his own descendants, all named Oroku Saki.
 * As in the comics, Vandal Savage in Justice League.

Real Life

 * In Georgia (the Eurasian one, not the North American one) men would pretend to be their fathers in order to dodge being drafted into the Russian army in the bad old days.