If we can trust the plot structure given by Proclus, the Nostoi closely corresponded to the scattered return accounts of Nestor, Menelaus, Odysseus and Agamemnon (and Proteus) in the Odyssey: following a quarrel caused by Athena, the Achaeans split up right at their departure from Troy and sailed off at different times and on different routes. Nestor and Diomedes who were first reached their homes safely. Menelaus who was second lost most of his ships and was driven to Egypt. Agamemnon and the Locrian Ajax sailed off last and met a storm that caused Ajax's death, while Agamemnon reached his home only to find his death by Aegisthus and Clytaemnestra. Later on Orestes took revenge, and Menelaus arrived at home.

Proclus includes two more storylines, untold in the Odyssey: Calchas and other heroes walked along the coastline of Asia Minor up to Colophon, where Calchas died; and Neoptolemus walked along the coastline of Thrace, joined the Molossians in Epirus and finally met his grandfather Peleus. But Proclus leaves no doubt that the Return of the Atreidai constituted the main storyline of this epic, occupying the beginning, the dramatic centre, and the end of the narrative.

Ps.-Apollodorus (Epit. 6.1–30) follows the same sequence of events as Proclus, with fuller wording and more details. He leaves out a few details told by Proclus, gives a sense of the full stories of Calchas and Neoptolemus which are just adumbrated in Proclus, and adds (parts of) storylines which clearly interrupt the stream of narrative. Apart from these additions, and with necessary caution, we may take his account as a fuller version of the same source used by Proclus: the text of the Nostoi, or rather a handbook prose version of it. As there are no other sources for the plot of the Nostoi, we should trust Proclus when he calls the epic he summarizes ‘The Returns, by Agias of Troizen, in five books’.