Commander Daniel "Dan" Martyn was the commanding officer of HMS Vigilant, one of Britain's four Trident ballistic missile carrying submarines which form the United Kingdom's nuclear deterrent. Martyn was born in Yeovil, Somerset. He received his school education at and Barton Peveril Sixth Form College. He subsequently completed degrees at Southampton and Keele Universities. He joined the Royal Navy in 1999. Martyn retired from the Royal Navy and the end of 2017. He is married and lives with his wife and twin boys in Glasgow.