In order to investigate a rare subspace phenomenon, Dax, O'Brien, and Bashir board the Runabout USS Rubicon, which is shrunk to four inches (10 cm) long. However, while investigating the phenomenon, the Defiant is boarded by Jem'Hadar.

The USS Defiant is sent on a mission to investigate a subspace compression anomaly. Probes which are sent into the anomaly are being shrunk down in size, and so the decision is to send the runabout USS Rubicon in, with Jadzia Dax (Terry Farrell), Miles O'Brien (Colm Meaney) and Julian Bashir (Alexander Siddig), in order to take readings. After sending the smaller vessel into the anomaly while attached on a tractor beam, the Defiant is attacked by a Jem'Hadar attack ship. Unable to raise their shields without disconnecting the tractor beam, the Defiant is disabled and boarded by Jem'Hadar soldiers. The tractor beam is disconnected, leaving the runabout in the anomaly where the Jem'Hadar cannot detect it.

Aboard the Defiant, the Jem'Hadar discover that the engines are damaged and the ship is unable to get underway to the nearest Dominion outpost. The Jem'Hadar leading Kudak'Etan (Scott Thompson Baker) celebrates victory, declaring that the new generation of Jem'Hadar born in the Alpha Quadrant are superior to those in the Gamma Quadrant. He overrules his Gamma-born second in command Ixtana'Rax (Fritz Sperberg), despite his status as an "honored elder" and greater experience. Kudak'Etan reports in to his Vorta superior, Gelnon (Leland Crooke), who orders him to prioritize repairs to the Defiant's warp drive and get underway to the Dominion outpost, while the Jem'Hadar ship departs for an attack on the Coridan system. Meanwhile, the three crew aboard the Rubicon set course for the Defiant, but as they approach the ship they discover that they have not resumed their previous size; the entire length of the runabout is now less than one foot long.

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