The Nature program, In the Valley of the Wolves, air this Sunday night on PBS (at least here in Idaho). The movie trailer included at the above link shows some amazing footage of wolves and other wildlife. It also features an interview with the filmmaker Bob Landis. I highly recommend you watch as Bob's work is amazing.
The movie trailer talks of Bob's dedication to filming, over 300 days a year for 4 years! I can attest to that fact that Bob has been out there filming on every occasion that I have been in Yellowstone National Park. I've watched some of his raw footage which is simply spectacular. This promises to be the best of his films on the Yellowstone wolves (this is his 3rd film on wolves).