Watergate (S04E07)

When the stargate won't open, trapping teams offworld, the SG-1 team investigates and learns that the Russians have their own stargate, apparently recovered from the sea after an Asgard ship crashed on Earth. The Russian stargate is locked open, maintaining a perpetual wormhole that defies explanation. At the request of Russian scientist Dr. Svetlana Markov, the SG-1 team is dispatched to the Russian stargate facility, where they make a shocking discovery: All the soldiers and scientists are dead and the stargate remains locked open, connected to a water-covered planet. Svetlana explains that the Russians had retrieved a sample of the water and found it has amazing properties, including the ability to emit significant levels of energy. That same water, however, seems to have disabled the drone, leaving it inoperable and sending transmissions that are keeping the stargate open. Dr. Daniel Jackson, Maj. Samantha Carter and Dr. Markov travel through the wormhole in a miniature submarine, in an attempt to recover the drone. The water brings the sub to a halt and begins to crush it, leaving the team unable to return through the stargate. Back at the Russian facility, Col. Jack O'Neill and Teal'c make their own shocking discovery: Inside a freezer is the frozen body of Col. Harry Maybourne, an SG-1 turncoat who apparently has been advising the Russians. As Maybourne begins to thaw, he comes back to life, spewing out gallons of water and a terrified warning. This may look like water, he says, but it's alive — and it's playing for keeps. (Metro-Goldwyn-Mayer (MGM))