Johnny Staccato is an odd duck in TV Land. It started in 1959, when Peter Gunn had been on the air for a year, and it seems to have given itself the challenge of out-Gunning Gunn. Thus while one show featured a private detective who hung out at a jazz club and dated the chanteuse, the other had a detective who actually sat in with the band. John Staccato, played by John Cassavetes, was the pianist at Waldo's, alternating with John Williams. Yes, that John Williams. And it was pretty vanguard jazz, aspiring to Dave Brubeck/Sonny Rollins levels of sophistication.
Cassavetes apparently didn't like the show, which may be one reason why its only season ended in March rather than May. It probably doesn't say much about the quality of the show, since he doesn't strike me as someone who'd want to be tied down to any TV show. He did still direct several episodes.
The quality of the episodes varies, but it has a pretty good batting average. Cassavetes's twitchy intensity was well suited to playing an eccentric gumshoe, believe it or not. They could also pull in some impressive guest stars. The second episode is an entirely obvious murder mystery, but features Martin Landau in a key role, providing a cool to Cassavetes's hot. And yes, offscreen wife Gena Rowlands shows up, in an episode that really drives home how different air travel was during the Eisenhower era.