Thismade-for-TVbio-picisaboutMarilynBell,aCanadianteenagerwho,in1954,wasthefirstpersontoswimacrossLakeOntario.ShewontheTorontoCanadianNationalExhibitionprizeafterFlorenceChadwick,athen-famousAmericanswimmerwhowaswidelyexpectedtowin,droppedoutinthemiddleoftherace.Halfofthisheart-warmingmovieisdevotedtothe21hourswiminwhi…