'Doctor Rhythm' is the worst film Bing Crosby ever starred in. Bing made this movie at his home studio Paramount during one of his best career arcs. The film has good production values, especially an impressive studio mock-up of Manhattan's Central Park. So, why is this film so painfully dull?<br /><br />Part of the problem is down to a weak score. The best song here is the insipid 'This Is My Night to Dream'. The script is even worse. Ostensibly, this movie is based on O. Henry's story 'The Badge of Policeman O'Roon'. In that story, a fictional war hero clearly based on Theodore Roosevelt impersonates his friend O'Roon (a mounted police officer assigned to Central Park) when O'Roon is unable to fulfil his duties: the brief story ends with one of O. Henry's trademark coincidences. If Paramount had actually filmed that story (which had barely enough plot to sustain a feature-length film), the result would have been better than this mess. Instead, we have a weird plot in which Crosby is a white-coated medico who illegally substitutes for his policeman friend, foot patrolman Andy Devine. The trim-figured Crosby looks dapper in a patrolman's tunic, but the huge slobby Devine looks so different from Bing that it's difficult to imagine Crosby substituting for Devine. And where did Crosby's character find a police tunic that fits him so well? The opening scene of this movie -- an illicit midnight foot-race in Central Park -- is fast-moving and shows promise, but the film's all downhill from there. I blame screenwriter Jo Swerling, a man of little talent who nevertheless got his name onto several prestigious projects. Swerling is contractually credited as co-author of the great Broadway musical 'Guys and Dolls', but that theatre classic does not retain a single word of Swerling's original (and worthless) script.<br /><br />The single worst problem with 'Dr Rhythm' is that someone at Paramount intended it to be a star vehicle for Bea Lillie, who only briefly appears alongside Bing in this movie. The Canadian-born Bea Lillie was married to a British peer and was often mistakenly assumed to be English. In the 1930s, Lillie was a huge star in Broadway musicals ... however, it's notable that she only starred in revues: shows with songs and skits but no plot. In the 1960s, Lillie played Madame Arcati in the Broadway musical 'High Spirits': this was her one and only success in a book musical. Lillie simply didn't have the acting ability to carry a narrative story. She starred in a semi-amusing silent, 'Exit Smiling', but most of her other film work is in supporting roles. I found her performance in 'Around the World in Eighty Days' deeply annoying.<br /><br />In 'Dr Rhythm', the banal plot and Bing's groaning are interrupted a couple of times so that Bea Lillie's specialities can get crowbarred into the movie. We see the routine in which she orders a double dozen double damask dinner napkins from a flustered shop clerk; Lillie had done this routine on Broadway but was careful never to perform it in Britain, where audiences knew that Lillie had stolen the routine from Cicely Courtneidge. We also get here another of Lillie's stage schticks: she is seen standing still on stage, wearing a formal gown that reaches to the floor, entirely concealing her feet. With much pomp, Lillie recites a dignified speech ... then she hikes up her skirt to reveal that she's wearing roller skates, and she skates merrily away. That's about as funny as this movie gets. It doesn't help that Lillie is physically unattractive. She looks like a cross between Norma Shearer and Jughead Jones. Mary Carlisle, Bing's love interest here, is blonde and pretty but dull as dishwater.<br /><br />Bea Lillie simply didn't have enough material to carry a starring role in a feature film, but there's enough of her on offer here to seriously weaken 'Dr Rhythm' as a Bing Crosby vehicle. Usually, when an important stage performer makes a rare screen appearance, I commend the film for preserving the performer's act. In this case, 'Dr Rhythm' serves the useful function of proving that Bea Lillie wasn't very funny. I can't recommend this movie to anyone but Bing Crosby completists, for whom I'll rate it just 1 point out of 10.