Book 15 describes the last part of the night of the thirty-fifth day, the thirty-sixth and thirty-seventh day, and the early morning of the thirty-eighth day; cf. Appendix A. We return to the ‘Telemachus’ storyline, which was dropped by the narrator in 4.624. Athena now carries out Zeus's injunction in 5.25–7 to escort Telemachus home safely: she gives him advice (28–42) and sends him a favourable wind (292–4); from 495 onwards he is back on Ithaca again. Meanwhile the narrator briefly switches back to Odysseus (301–495); the use of the ‘interlace’ technique † at such short intervals prepares for the merging of the ‘Telemachus’ and ‘Odysseus’ storylines in the next book (cf. Appendix B).

In accordance with the ‘continuity of time’ principle †, the same amount of time has elapsed for Telemachus as for Odysseus (who occupied the stage during the last ten books), viz. twenty-nine days. That a considerable time has passed is suggested by Athena coming ‘in order to remind (Telemachus) of his homecoming’ (3), rebuking him because ‘it no longer becomes him to wander away from home’ (10), Telemachus asking Menelaus ‘to send him on his way now at last’ (祰δηνũν: 65, and cf. 祰δη in 66 and 88; cf. 10.472, where Odysseus' comrades beg him to remember home ‘now at last’ after a year's stay with Circe), and being greeted by Eumaeus as a son who has been away for ten years (16.18); cf. also the anticipation of an absence of ‘eleven or twelve days’ in 2.374 and 4.588.