A particularly absurd installment in the series, but not an un-entertaining one. Just be prepared for courtroom sequences that make the one in Duck Soup look like a documentary on proper court procedure.
Shayne is a juror on a murder case(!); a pretty young woman is accused of murdering her fiance, and a showgirl who worked with the guy saw the accused leave the dead man's apartment, you see. A butler that is the woman's alibi is testifying when somebody bursts into court, tosses a dagger, and hits him right in the heart. Well, here's where the film heads into territory that Rod Serling should be guiding us through: Shayne, sensing a reward, leaps from the jury box and steals the murder weapon(!!) so that he can investigate. The jury is sent back into sequester for the night (no, not dismissed) and he drugs his roomie (after the two of them discuss the case, an obvious no-no), and Shayne ducks the sheriff who's watching over the jury, picks up reporter Marjorie Weaver (in her third appearance in the series and her third different character) and they spend the night together snooping, including visiting a jeweler in his home at apparently 3:00 a.m. Oh, and they have to keep ducking Phil Silvers, a free-lance photographer trying to snap a picture of the rogue juror who is traipsing around town all night. The next morning, back in court, Shayne leaps from the juror's box and, with the judge's enthusiastic support, begins cross-examining witnesses himself.
As Michael Shayne movies, go, this is one of the better ones, which says a lot.
P.S. The title is meaningless in the context of the film.