The installation of Gowron as High Council leader has provoked unrest on the Klingon homeworld. Lursa and B’Etor, sisters from the disgraced House of Duras, are willing to deal with the Romulans to regain their power. The Romulan Empire, eager to disrupt the Federation/Klingon Alliance, secretly backs the Duras sisters, providing supply's and weapons. The dilemma is: How can Starfleet prove the presence of cloaked Romulan ships? Chief Engineer Lieutenant Geordi La Forge provides a bold plan involving dozens of Starfleet vessels, utilizing faster-than-light tachyon beams. Geordi's idea is to position at the predetermined intervals near the Klingon/Romulan border. Then each ship will send out a tachyon beam to the ships nearest to them, thereby creating a tachyon net. The theory is that when a cloaked Romulan ship interrupts one of the invisible tachyon beams, sensors will report the Romulan ships location. At this time, Starfleet vessels are scattered throughout the quadrant and most are much more than a day’s travel from the Klingon Romulan border. However, every available ship is put to work. In all, 20 Starfleet ships participate in Geordi's Tachyon web. Command crews from ships prematurely out of Spacedock and construction yards are brought up to strength alongside the U. S. S. Enterprise NCC-1701-D. Even Data is eventually given command of a ship, the U. S. S. Sutherland.

With the fleet in place at the border, the tachyon beams are activated; the net is thrown. Geordi's theory is proved when five cloaked Romulan ships are detected. The Romulan force, led by Commander Sela, thought to be the daughter of Tasha Yar soon discovers the Tachyon net. However, she is at a loss as to how to avoid it. Evasion is critical since additional Romulan supply ships are approaching, and the Romulans are desperate to keep their involvement secret. All Romulan ships hold their positions waiting for a new plan. Captain Picard decides to break the statement by allowing one of his ships to accidentally create a hole in the Tachyon net. However Sela recognizes the trap and refuses to bite. Sela reasons a part of the Tachyon net that can be negated by flooding it with a massive tachyon pulse. The interference will provide her ships with safe, undetected passage. Her target is the area where the Sutherland is positions-Data’s ship.

Data, at his first command-the first command ever for an android-is saddled with a resentful crew who doesn’t trust a machine. But he is resolute, and not about to give up command so easily. When Sela’s tachyon pulse hits, the sensors on Starfleet ships are jammed and can’t detect Romulan vessels passing through their Tachyon beams. Sela's ships begin to escape as Picard orders all Starfleet ships to reassemble the net in front of the Romulan vessels. Data ignores Picard's orders, realizing each Romulan ship, now covered with subatomic tachyon signature. He orders the Sutherland's sensors to detect ionized particle traces. Using this approach, he is able to get a fix on the Romulan ships. Then after he orders his crew to emit a level-six-high energy burst, the Romulan tachyon particles are targeted. Ignoring Picard's demands to rejoin the net, Data orders the Sutherland's torpedoes to be fired. The Reconfigured torpedoes light up the Romulan ships within the sensor haze. With the whereabouts of a number of her vessels now revealed, Sela quickly withdraws Romulan support and leaves the Duras sisters to fend for themselves.