Season 5 of Stargate Atlantis will involve a number of changes, not least of which is a brand new expedition commander. Actually, he's not brand new at all – Richard Woolsey (played by Robert Picardo) has been around since season 7 of Stargate SG-1, evolving from a stiff stickler for protocol to someone who's starting to understand the real world doesn't always line up with the rule book.

Picardo talked with me about the forthcoming fifth season of Atlantis and how Woolsey deals with the uncharted territory of giving orders instead of reviewing them. He also talks about how his development of Woolsey has been affected by his past experiences, both as Woolsey and in other roles on Star Trek: Voyager, China Beach, and a Showtime sitcom where he had to sign a nudity clause – wait, what?

For my interview with Robert Picardo, click here. (There's an image gallery, too.) For highlights of what's expected in season 5, check out this preview.

Looming over the entirety of season 4 of Stargate Atlantis were two unwelcome character deaths. The much-loved Dr. Carson Beckett (Paul McGillion) had been killed off late in season 3 ("Sunday"), arousing a storm of fan protest, and the leader of the Atlantis expedition, Dr. Elizabeth Weir (Torri Higginson), sacrificed herself to destroy the Replicators in the second episode of season 4 ("Lifeline"). Reports swirled that the current lead producers of the series, including Martin Gero, felt that Dr. Weir was a flawed character and that Higginson had been let go from the series for that reason.

The great thing about DVD sets is that they give you an opportunity to view an entire season as an entity, with helpful explanations in the form of featurettes and commentary to actually provide some answers to that oft-repeated refrain, "What were they thinking?" And this DVD set in particular, the complete season 4 of Atlantis, continues the fan-conscious franchise's effort to provide as many of those answers as possible, by providing commentary tracks for all of the episodes, "Mission Directive" director overviews on key episodes, and overall featurettes on what's new and different about the season as a whole.

• My review of Stargate Atlantis: The Complete Fourth Season