The Trials of Oscar Wilde (1960)  

Also released under the title The Man With the Green Carnation, this  well-regarded film stars Peter Finch as Oscar Wilde and deals with Wilde's prosecution for homosexuality.  Booth plays  a minor role as Alfred Wood, the impoverished former valet of Wilde’s boyfriend.  Wood tries to blackmail Wilde with a compromising letter. Instead, the immensely urbane and self-confident Wilde turns the whole thing into a joke at Wood’s expense, then gives him some money anyway and asks him out. 

“There’s a fascinating charm to your halfhearted criminality,” Wilde says, “You must lead an exciting life.”  Wood replies, “There’s good and bad in all of us, sir”--a quintessential James Booth character and moment!

Booth makes another brief appearance near the end of the film in a courtroom scene.  Wood approaches the witness stand to  deliver testimony about his  gay date with Wilde,  but the scene ends before Wood says anything.