I picked this up while browsing at the library, mainly because I like Lily Tomlin. But after seeing it, I thought it was only so-so.
The movie was made in 1976, and is a homage to detective movies of the 1940s. In addition to Art Carney and Lily Tomlin, it also stars Bill Macy (of "Maude, " not to be confused with William Macy of "Fargo"). It was produced (though not directed) by Robert Altman.
With so much talent and such an interesting premise, I thought this was going to be great. And it had its moments -- there was a great chase scene, with Lily Tomlin driving a van across people's lawns, and there were moments of clever dialogue -- but overall it was a bit disapointing.
The mystery plot itself was not that interesting, and the characters -- Art Carney's old-guy has-been detective and Lily Tomlin's young space-cadet hippy, along with assorted bad guys -- were too broadly drawn to be completely believable, but not really funny enough to be a great spoof either.
The way the Carney character and the Tomlin character worked together as an "odd couple" was pretty good though. That was the best thing about the movie.
There isn't much in the way of special features, just a trailer and a short appearance that Lily Tomlin made to promote the film on the Dinah Shore show.