"Lonely Among Us" is the seventh episode of the American science fiction television series Star Trek: The Next Generation that originally aired on November 2, 1987, in broadcast syndication in the United States. It was written by D. C. Fontana, based on a story by Michael Halperin. It was the first episode of The Next Generation to be directed by Cliff Bole.

Set in the 24th century, the series follows the adventures of the crew of the Starfleet starship Enterprise-D. In this episode, as the ship is en route to an interplanetary conference with delegates from the Selay and Antican races on board, a non-corporeal alien entity takes possession of various Enterprise crew members, including Captain Jean-Luc Picard (Patrick Stewart).

This episode marked the first appearance of Star Trek: Deep Space Nine recurring cast member Marc Alaimo in a Star Trek series, as well as the second appearance of Colm Meaney who would later play The Next Generation and Deep Space Nine character Miles O'Brien. The Antican and Selay make-up were created by Michael Westmore from designs by Andrew Probert. Following the airing of the episode, fans wrote in to complain about a scene referencing cannibalism. Reviews were mostly negative, with criticism directed at the writing in particular.

The Enterprise is en route to the planet "Parliament" with delegates from two warring planets in the Beta Renner system, the reptilian Selay and the canine Antican, when the ship encounters a strange energy cloud. Unseen by the crew, Lt. Worf (Michael Dorn) is hit with a strange energy discharge as the ship passes the cloud, causing him to become violent. Doctor Beverly Crusher (Gates McFadden) sedates Worf and brings him to the sickbay, but is also infused with the energy as she examines his body. Crusher begins to act oddly to those around her and goes to the bridge, asking questions about the ship's navigational functions. When she questions Lt. Cdr. Data (Brent Spiner) at one of the science stations, the energy sparks between her and the console, leaving her confused as to why she is on the bridge.

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