Guest Stars Eric Mason as C.P.O. Smedley Donald Sumpter as Commander Ridgeway Clive Morton as Trenchard Edwin Richfield as Captain Hart Pat Gorman as Sea Devil Norman Atkyns as Rear Admiral Peter Forbes-Robertson as Chief Sea Devil Christopher Wray as Ldg. Seaman Lovell Martin Boddey as Walker Neil Seiler as Radio Operator June Murphy as 3rd Officer Jane Blythe Terry Walsh as Castle Guard Barclay Royston Tickner as Robbins Stanley McGeagh as Castle Guard Drew Brian Vaughan as Lt. Commander Watts Rex Rowland as A/B Girton John Caesar as C.P.O. Myers David Griffin as Lt. Commander Mitchell Colin Bell as C.P.O. Summers Brian Justice as Castle Guard Wilson Alec Wallis as Ldg. Telegraphist Bowman Hugh Futcher as Hickman Declan Mulholland as Clark
