Friday night A & E network premiered the latest season of MI-5, known in England, where the show originates, as Spooks.

The show focuses on, as the American titles states, MI-5, the England’s domestic intelligence service (the equivalent of the U.S.’s CIA), or more rightly, single team at Five. Think 24 without the superhero character Jack Bauer has become since that show’s inception. Additionally, MI-5 tends to have more reality-based plots than 24’s outlandish world destruction ones. As such, MI-5 has a far more gritty, far more realistic sensibility to it. The characters here are far more fallible.

Over the course of its existence the cast of MI-5 has changed significantly, with the main three characters dropping out and being replaced by new individuals (as well as other additions and subtractions to the supporting cast along the way). The episode this Friday actually begins at the funeral of one of the original characters, Danny Hunter (played by David Oyelowo, though he doesn’t appear in the episode, only a picture of him does). The mourning is quickly interrupted however when a bomb explodes in London killing over 30 people. Danny’s colleagues file out of the church and the new season begins in earnest.

In true MI-5 fashion, not only do they spend a lot of time in front of the computer trying to sort out video and other hints as to the goings on, they take shots at the “special relationship” England has with the United States, and find themselves in grave personal danger when in the field. It all works extremely well.

Save maybe this last point. The new characters in the show have not yet been as completely fleshed-out as the old ones. Not only do we know far less about them, but I personally am far less disposed to develop the same affinity for them as I did with the first cast.

When the first group of characters started to leave the show I was hugely disappointed to see them go, particularly Tom (played by the absolutely brilliant Matthew MacFadyen). If the cast is completely disposable it is far more difficult to convince the audience to truly get involved in their lives, and consequently the viewer is not as invested in the character’s surviving through the episode (after all, the producers will simply right in a new one next week). This is felt even more so for a show coming across the ocean from England, where viewers will only be treated to at most a dozen episodes before it disappears for at least a year and often longer than that (cable networks in this country also tend to produce shows in this manner). This difficulty is far more simple to overcome in a comedy, such as Coupling, where Jeff Murdock (Richard Coyle) left after the third season to be replaced by Oliver Morris (Richard Mylan) in the fourth. As Coupling is far more light-hearted, the viewer (at least this one) needs to invest less emotionally in order to be satisfied.

Even so, Adam Carter (Rupert Penry-Jones) is a worthy successor to Tom and after only one episode the new season seems to firing on all cylinders: there is a mole in the service (something of an old storyline for a show like this one), there is an operative being held at gun point, Harry Pearce (head of the department) has a secret, and the episode will be continued next week.

Despite any weakness in developing the newer cast members, MI-5 is well worth checking out for any fan of the genre.