There is an urgent need to understand how organisms respond to multiple, potentially interacting drivers in today's world. The effects of the pollutants anthropogenic sound (pile driving sound playbacks) and waterborne cadmium were investigated across multiple levels of biology in larval and juvenile Norway lobster, Nephrops norvegicus under controlled laboratory conditions. The combination of pile driving playbacks (170 dBpk-pk re 1 μPa) and cadmium combined synergistically at concentrations >9.62 μg[Cd] L−1 resulting in increased larval mortality, with sound playbacks otherwise being antagonistic to cadmium toxicity. Exposure to 63.52 μg[Cd] L−1 caused significant delays in larval development, dropping to 6.48 μg[Cd] L−1 in the presence of piling playbacks. Pre-exposure to the combination of piling playbacks and 6.48 μg[Cd] L−1 led to significant differences in the swimming behaviour of the first juvenile stage. Biomarker analysis suggested oxidative stress as the mechanism resultant deleterious effects, with cellular metallothionein (MT) being the predominant protective mechanism.