Imperator shrimps (Periclimenes imperator) are frequent celebrity hitchhikers on slow-moving invertebrates. Sea cucumber hosts are akin to drab-coloured, sluggish buses compared with host nudibranchs, which move about like colourful taxicabs. The toxic nature of nudibranchs offers safe transport in a dangerous sea in exchange for on-the-go janitorial services to remove gunk, goo and other undersea detritus from the velvety skin of its host. I was surprised and pleased to see a pair of imperator shrimps conducting business among the delicate and frilly gills of a large Spanish dancer that was preparing to lay eggs on a coral ledge. The pink-and-red polka-dotted pair resembled Balinese art in this moonlit sea off Tulamben, Indonesia.