Sheldon Lawrence is "Danny", an American freestyle swimmer who comes to Kent to to swim the English Channel - all 21 miles of it - over to France. He is trained by his determined brother "Griff" (John Ireland) and it's at one such training session they encounter "Kitty" (Joy Webster), also planning to make the trip - and so they decide to team up. She is sponsored by "Seymour" (Derek Bond), a married man with whom she is having an affair. She gives him an ultimatum before she sets off on her task, a pea soup fog sets in and next thing... "Danny" is sure foul play is involved and he sets out to find out - at no small risk to himself - what actually happened. We know all along who did what to whom, so there's no jeopardy with his investigation, but the story makes for quite an entertainment 80 minutes; the characterisations are quite engaging and the romance is kept strictly to a minimum. Eagle eyed amongst us may spot soon-to-be "Capt. Mainwairing" (Arthur Lowe) in his garage, and there are a couple of decent supporting roles for Leslie Dwyer as her coach "Bill" and for hotel receptionist Maureen Connell ("Shelley"). Not a film that will remain in the memory, but I still quite enjoyed it.