Dinner?

If you don't want to buy a flopping fish in the market (they'll kill it for you and cut off the head, but only if you ask), then you can buy it at Tesco Lotus (Thailand's Walmart.)

They are just laying out on ice, along with piles of ground pork, chicken legs, chicken feet, and all sorts of other pre-delicious, post-live-animal food. Use the tongs to put what you want in a bag and take it home for dinner.