This Week (Jan. 5 - 12)

New episodes this week include the series finale of Stargate Atlantis, plus Knight Rider, Ghost Whisperer, Sanctuary, and Legend of the Seeker.

Sci Fi is celebrating Stargate Atlantis by showing classic reruns all week during its daytime marathon slots, including the entirety of season 5 on Thursday and Friday. See the listings for details.

Here's the skinny on this week's new episodes:

• Knight Rider "Don't Stop the Knight" 1x10. Mike and KITT rev up to rescue a snatched foreign ambassador (Vanessa Williams) from the clutches of a deranged terrorist. Elsewhere, Sarah and Doctor Graiman team up to repair a damaged robot.
• Ghost Whisperer "Life on the Line" 4x11. Melinda tries to bring healing to a family suffering in the aftermath of a freak accident. Elsewhere, Delia endures her first haunting.
• Stargate Atlantis "Enemy at the Gate" 5x20. Todd warns Atlantis about a sophisticated hive ship and encourages the team to attack the vessel before it can pose a threat to Earth in the series finale. Amanda Tapping, Christopher Heyerdahl.
• Sanctuary "Revelations: Part 2" 1x12. Conclusion. Henry and Ashley are held captive by the Cabal. Elsewhere, Magnus and her allies try to navigate the ruins of an ancient city.
• Legend of the Seeker "Denna" 1x08. A Mord'Sith turns Richard's powers against him, testing the Seeker's will.

Coming next week: The season premiere of Kyle XY and the long-awaited returns of Battlestar Galactica, Smallville, and Supernatural.