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Terrestrial snails (Gastropoda) possess Cd-selective metallothioneins (CdMTs) that inactivate Cd²⁺ with high affinity. Most of these MTs are small Cysteine-rich proteins that bind 6 Cd²⁺ equivalents within two distinct metal-binding domains, with a binding stoichiometry of 3 Cd²⁺ ions per domain. Recently, unusually large, so-called multi-domain MTs (md-MTs) were discovered in the terrestrial door snail <i>Alinda biplicata (A.b.)</i>. The aim of this study is to evaluate the ability of <i>A.b.</i> to cope with Cd stress and the potential involvement of md-MTs in its detoxification. Snails were exposed to increasing Cd concentrations, and Cd-tissue concentrations were quantified. The gene structure of two <i>md-MTs</i> (<i>9md-MT</i> and <i>10md-MT</i>) was characterized, and the impact of Cd exposure on <i>MT</i> gene transcription was quantified via qRT PCR. <i>A.b.</i> efficiently accumulates Cd at moderately elevated concentrations in the feed, but avoids food uptake at excessively high Cd levels. The structure and expression of the long <i>md-MT</i> genes of <i>A.b.</i> were characterized. Although both genes are intronless, they are still transcribed, being significantly upregulated upon Cd exposure. Overall, our results contribute new knowledge regarding the metal handling of <i>Alinda biplicata</i> in particular, and the potential role of md-MTs in Cd detoxification of terrestrial snails, in general.