During World War II he went back to the Navy as senior officer of the 22nd Anti-Submarine Group, Mediterranean Fleet. He was transferred, in 1943, to the Royal Navy and sent to Staff College at Greenwich, England. For the rest of the war, he was commanding officer of HMS Walker, a destroyer principally employed on convoy-escort duty in northern waters. He was awarded the Distinguished Service Cross.
Since he returned to South Africa, Mr. Trew has lived in the country outside Johannesburg. He began writing at night as a cure for insomnia. Two Hours to Darkness is his first novel.