Bing Crosby, Mary Martin, Gloria Dickson At Del Mar Horse Race

The video captures a day at the Del Mar racetrack, highlighting Hollywood stars like Gloria Dickson and Bing Crosby. It features the excitement of the race called 'Rhythm on the River' and the thrilling moments as horses compete, with Mary Martin being a notable attraction.

Which Hollywood star is mentioned as having a sorry defeat?

What type of excitement is described in relation to the race?