Publisher's summary Edit
While the Doctor advises the Captain on navigational matters, Ace joins in a daring mission to rescue sailors in the water. With German planes overhead, no-one's survival is guaranteed...
- Ace's mother Audrey Dudman watched World War II naval films on Saturday afternoons growing up.
- The Doctor's pockets contain a half eaten toffee apple, marbles and a paperweight.
- Jimmy Mayhew joined the Royal Navy because his home was bombed during the Blitz.
- The United States is in the process of developing sonar.
- Ace knows first aid.
- This story was available for download only.
- Captain Fitzgerald assumes that the Doctor is working at Bletchley Park. During his sixth incarnation, he worked in Hut 12A at Bletchley Park in 1944. (AUDIO: Criss-Cross)