This paper examines a neglected episode in the reception of Lucretius by Seneca through the mediation of Neronian poetry, focusing on Seneca’s sole explicit quotation of Nero’s verse in the Naturales Quaestiones (QNat. 1.5.6-7). Set within a technical discussion of the rainbow, the quotation—likely drawn from Nero’s lost Troica—reveals a dense network of Lucretian, Epicurean, and Stoic intertexts. The paper argues that Seneca’s apparent praise of Nero’s poetic elegance conceals a complex strategy of doublespeak. Nero’s Lucretian imagery, deployed by a fictional adversarius to support a chromatic (rather than catoptric) explanation of the rainbow, aligns the emperor’s poetry with Epicurean meteorology and with an ultimately erroneous physical theory rejected by Stoicism. By situating this citation within broader debates on optical illusion, color, and epistemology—from Hellenistic scepticism to Lucretius’ atomism—the paper shows how Seneca subtly undermines Nero’s solar self-fashioning. The dove of Venus, echoing Lucretian atomic imagery, takes on “color, not image” (colorem, non imaginem), thereby exposing the instability of poetic imitation and political symbolism alike. Seneca’s engagement with Nero thus emerges as a sophisticated instance of mediated Lucretian reception, in which intertextual allusion becomes a vehicle for philosophical critique and oblique political commentary.