The AV Club has a great article on The Middleman, going through one episode and talking about why it was so good, with lots of embedded clips.
Here’s the best way to describe The Middleman: Imagine if Joss Whedon and Amy Sherman-Palladino collaborated on a secret-agent/science-fiction/superhero script, then handed it off to be directed by John Carpenter, with cinematography by Barry Sonnenfeld. Created by Javier Grillo-Marxuach . . . , The Middleman stars Natalie Morales as lovelorn art student Wendy Watson, a.k.a. “Dub-Dub” or “Dubby.” She gets recruited by a straight-arrow covert operative known only as “The Middleman” (played by Matt Keeslar) to join an organization that’s been using comically fake IDs and advanced technology to combat “threats intra-, extra-, and juxta-terrestrial” for generations. Whenever aliens infiltrate, super-apes join the mob, sorority houses get haunted, or trout-craving zombies arise, Middlemen rush to the rescue, with weapons drawn and rapid-fire repartee at the ready.
Coincidentally, a few days ago I decided it was time to watch the series straight through (Chad and I watched about half of it a couple years ago and for no reason other than lack of time never finished). The Middleman is occasionally slightly creepy in the pilot, but it doesn't last and really, the show had me from minute one, when Wendy answers the phone at her temp job "Thank you for calling A.N.D. Laboratories, rescrambling your D.N.A., how may I direct your call?"
It is very silly, it has a woman of color lead and a central female friendship, it has adorable time-and-date lines ("The Underworld. Time has no meaning or relevance."), it is geektastic in the extreme but not in a way that ever made me feel I was missing something, and it is entirely worth the ten minutes of your time to read the article and watch the clips to see if you want to watch the rest of it.