In Routine Patrol, Margaret Laretski was a Scottish woman whom Ginger discovered hiding out on a small uninhabited island among the Scottish Western Isles.
While out on a routine patrol over the west coast of Scotland, Ginger spotted some smoke rising from a small uninhabited island. When he approached for a closer look, he found that the fire was quickly doused. Biggles sent Ginger and Bertie for a second look at night and they returned confirming that someone had a fire going on the island.
Two days later, Biggles and co. landed on the island in a borrowed service helicopter but found nothing. As they departed, Ginger opted to remain behind for a closer look, to be picked up the next day.
After the helicopter left, Ginger found Margaret cooking something over a fire at the bottom of a corrie. At first Margaret held him up with a revolver but he persuaded her to let him approach to talk.
It turned out that Margaret had been on the island for almost three months. She had been hiding from the police because she believed she had killed her abusive husband who had beaten her and had killed her son in a fit of temper. On the island she had been supplied by a friend on the mainland and their plan was to wait for the murder to be forgotten before fleeing to Australia.
Ginger told Margaret that she didn't kill her husband, a Pole. She had only knocked him out and this actually helped the police to apprehend him: they had been looking for him for years for the murder of his first wife. The man had already been tried and hanged under his real name. He had married Margaret under an assumed name and that explained why Margaret never knew what happened.