Castlepook Cave is compelling because it resists a simple narrative: mammoth, reindeer and hyena remains indicate open habitats, yet mixed deposits prevent their treatment as one contemporaneous community. A possibly modified reindeer bone raises the prospect of a brief human visit without demonstrating settlement or a route across the Irish Sea. This distinction matters when Ireland is compared with Upper Palaeolithic Europe, whose richer cultural evidence could encourage unwarranted assumptions. How should researchers weigh environmental plausibility, taphonomic caution and comparative evidence when considering whether people briefly reached Ireland during Marine Isotope Stage 3, and what discoveries might clarify that possibility?