Cut the bacon first lengthwise, then across - i.e. you should get 4 thin strips per rasher.
Cut the fish into 2-3 cm cubes. Roll up each fish piece in a bacon piece (starting at one end).
Lightly oil the base of a frying pan and heat it. When it's hot, put the wraps in the pan - the overlaps of the bacon should be underneath. After a minute turn them over and cook for a minute, then roll them on their side and cook again. When the wraps are crispy all over, move them onto a plate, lined with paper kitchen towel.
Alternatively put them on a lined baking tray and grill them in the oven until crispy.
Serve them with toothpicks or as finger-food.