Related Clues:

• Went under
• Took the plunge
• Declined sharply
• Plunged
• Jackknifed, e.g.
• Emulated Louganis
• Went scubaing
• Went off the deep end
• Made a splash?
• Did a jackknife, say
• Did a gainer, say
• Jackknifed
• Hunted for pearls, maybe
• Sought pearls, perhaps