S4E24 · The Mind's Eye

Geordi La Forge, en route to Risa for an academic conference, is captured by Romulans. While an impostor that looks like La Forge is sent to Risa, the Romulans restrain La Forge and exploit his VISOR—a device that gives the blind La Forge vision—to tap into his visual cortex, giving them a limited form of mind control over him. After several days, La Forge's mind is wiped of his capture but given memories of going to Risa, and he is put back aboard his shuttle, to return to the Enterprise. He arrives as the Enterprise crew are working with the Klingon Ambassador Kell to deal with a rebel movement on Krios, a Klingon colony near the Federation border. The governor of the colony, Vagh, asserts that the rebellion is being aided by the Federation, thus requiring the Federation's presence to resolve.

At the colony, Vagh shows Captain Picard and Kell that Federation-designed weapons have been taken from the rebels. Picard orders his crew to investigate. Lt. Commander Data detects strange E-band radiation but cannot identify the source. He and La Forge also discover the apparent Federation weapons were replicated using Romulan technology and powered by Romulan energy cells. Later, under the direction of his controllers, La Forge unknowingly transports a case of Federation weapons from the Enterprise to the rebel base, and then subsequently erases the logs. Vagh, monitoring the transport, immediately accuses the Enterprise of deception.

Data and La Forge review the transport logs but that, even though the transport originated from the Enterprise, the records have been erased; La Forge observes that only he, Data, and two other crewmembers could have falsified the logs in that manner, and he is the only one with no alibi. Again outside of his control, La Forge enters Kell's quarters on the Enterprise, where Kell orders La Forge to assassinate Vagh in a public setting before witnesses in such a manner as to utterly convince Vagh's people of Federation involvement.

At Kell's suggestion, Picard invites Vagh aboard the Enterprise to observe the investigation into the unauthorized transport. As Picard takes Vagh around the ship, Data discovers that the E-band radiation is coming from aboard the Enterprise and that La Forge never made it to Risa. He orders Security Chief Worf to immediately detain La Forge. The assassination attempt is blocked, and Data arrives to explain the situation, saying that the limited transmission range means the device controlling La Forge must either be in Picard's or Kell's possession. Kell refuses to undergo a search, but Vagh offers to take him to the colony to do so there.

Fearing the consequences of being investigated by his own people, Kell quickly requests asylum aboard the Enterprise, which Picard says they will consider after his name is cleared of any wrongdoing by the Klingons. Kell is taken away by Vagh's guards. La Forge is cleared but struggles to understand what happened to him.