I wish I had been able to see this show.
The Zoo Gang was a 1974 ITC series that ran for just six episodes, airing in the spring of '74. An eclectic ensemble cast, including Brian Keith (ex-Family Affair), Barry Morse (ex-The Fugitive), and John Mills, brought to life Paul Gallico's tale of a team of World War II resistance fighters who reunite 30 years later to fight crime.
A year later, The Zoo Gang aired on NBC as a 3-night miniseries, and that's the last anyone's seen of it here, as it's on DVD in the UK only.
The other notable thing is that the theme music was composed by Paul & Linda McCartney, and performed by McCartney & Wings.
The Zoo Gang was the first of Gallico's works to be adapted into series form of any kind since The Adventures of Hiram Holliday some 20 years earlier. I believe there've been one-shot adaptations for the likes of Hallmark Hall of Fame, but there has to be more in the library waiting to be brought to life. Of course, if the Zoo Gang were to be revived today, the setting would understandably be updated to reflect more recent times.
This was Barry Morse's 2nd series for ITC, coming a couple of years after co-starring with Gene Barry in The Adventurer, and by the time NBC picked up Zoo Gang, Morse had moved on to Space: 1999.
Now, let's scope the intro and that kickin' Wings beat.