Agrajag is a piteous creature that is continually reincarnated and subsequently killed, each time unknowingly, by Arthur Dent. Agrajag is first identified in the novel Life, the Universe and Everything, but it is revealed that several of Arthur's encounters in the first and second novels (and in previous chapters of the third) were with previous incarnations of Agrajag. The first occurs in the novel The Hitchhiker's Guide to the Galaxy, when a bowl of petunias is suddenly yanked into existence miles above the planet Magrathea, and begins falling, having only time to think, "Oh no, not again," before crashing to the ground. The reason behind the bowl's lament is revealed in the novel Life, the Universe and Everything, when Agrajag identifies the bowl of petunias as one of his prior incarnations, and tells Arthur that he had seen his face in a spaceship window as he fell to his doom. In another incarnation, Agrajag was a rabbit on prehistoric Earth (during the time period recounted in the novel The Restaurant at the End of the Universe) who was killed by Arthur for breakfast and whose skin was fashioned into a pouch, which is then used to swat a fly who also happened to be Agrajag. In yet another, near the beginning of the novel Life, the Universe and Everything, Agrajag is an old man who dies of a heart attack after seeing Arthur and Ford materialise, seated on a Chesterfield sofa, in the midst of a match at Lord's Cricket Ground.
Eventually, Agrajag wishes to take revenge on Arthur Dent, diverting his teleportation to a Cathedral of Hate. However, in the process of explaining his reasons for hating Arthur he mentions "Stavromula Beta," where Arthur had ducked to avoid a shot fired by an assassin, which then had hit and killed Agrajag instead. Arthur, having never been to Stavromula Beta, has no idea what Agrajag is talking about, and Agrajag realises that he's brought Arthur to the Cathedral too early. He tries to kill Arthur anyway, and once again dies at Arthur's hands while Arthur is defending himself, but not before setting off the explosives intended to kill Arthur by triggering a massive rockfall. Arthur escapes the rockfall unharmed.
For the next few years Arthur travels the universe, secure in his knowledge that, no matter what happens, he cannot die at least until after he survives his assassination attempt at Stavromula Beta. In the novel Mostly Harmless Arthur's daughter Random Frequent Flyer Dent holds him hostage in a London club. When she fires her weapon Arthur dodges, causing the bolt to pass over his head and hit the man standing behind him. Earlier the victim (Agrajag) had dropped a book of matches which revealed the owner of the nightclub to be Stavro Mueller, and the name of the club to be Beta. Thus, what Arthur believed to be the name of a planet was actually the name of the nightclub, and Agrajag has died once again. Because of this, Arthur is now able to die as well, which, thanks to the Vogons, he does a few seconds later.
In fit the fifteenth of the radio series, Douglas Adams plays Agrajag, having recorded the part for an audiobook version of the novel Life, the Universe and Everything. Producer Dirk Maggs added a suitable voice treatment, and Simon Jones as Arthur Dent recorded his lines opposite the pre-recorded Adams. Adams was thus able to "reincarnate" to participate in the new series.
At the end of the novel And Another Thing..., Arthur Dent's extreme bad luck in life coupled with cosmic balance mean that as he materialises on a planet shortly before Vogons are due to destroy it, Agrajag wakes up from a coma after six months having won the lottery and been recognised by a long lost love whilst on "Celebrity Coma." This event presumably leads to cosmic balance ruining his other lives for the benefit of Arthur Dent.
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