Put the shallot in a bowl with the wine and leave it while you prepare the seafood. Finely chop the oysters, making sure you don’t lose any of the juices, and tip into a bowl with the juices. Finely chop the scallops and smoked salmon and add them to the bowl. Clean the oyster shells and put 3 on each plate (or the lot onto a tray if you want to make these 2-3 hours ahead.)
Drain the shallot and add it to the bowl, then add I tbsp olive oil and a squeeze of lemon and mix well. Cut the lemon into slices and push one under each oyster shell to stabilise it. Spoon some mixture into each shell along with chives, freshly ground black pepper and a small amount of roe until all the shells are filled. Cover and chill until you need them, but serve within 3 hours.
Serve with melba toasts to spoon the mixture onto, and allow them to sit for 10 minutes to take the chill off.