"She's a predator."
The Scimitar was the keystone of Shinzon's plot to assassinate the Romulan Senate and assume the role of Praetor of the Romulan Star Empire, something he could not achieve without the support of the Romulan military. The Scimitar helped prove Shinzon's ambitions of attacking the Federation and ending the period of peace that had frustrated some Romulan generals.
The Scimitar was destroyed by the crew of the USS Enterprise-E at the Battle in the Bassen Rift, where it inflicted severe damage on the Starfleet ship and Romulan reinforcements. Lt. Commander Data of the Enterprise managed to board the Scimitar, where he transported Captain Picard off the ship. Picard had originally gone to the ship to disable the thalaron generator, but was unsuccessful. After he was gone, Data fired his hand phaser into the thalaron intermix chamber, only two seconds before the weapon would have fired. This caused a chain reaction which destroyed both the ship and Data. (Star Trek Nemesis)
The Scimitar's cloaking technology was, in the words of Geordi La Forge, "perfect." It emitted no tachyons and left no residual anti-protons, the two ways that a cloaked ship could be tracked and located. Thus, when cloaked, the Scimitar was virtually impossible to find. Only a chance hit by an opposing ship's weapons or by targeting where the Scimitar's shots come from could reveal its location, temporarily disrupting the cloak. The Scimitar could even deploy its weapons and deflector shields and travel at high warp speeds while cloaked, actions which, with less-advanced cloaking technology, necessitated de-cloaking or reduced the effectiveness of cloaking. Its maximum warp factor when cloaked was more than that of Starfleet's Template:ShipClass starship.
Weaponry and military equipment
The Scimitar was designed for war. With 52 disruptor banks and 27 photon torpedo bays, it was ready for nearly any battle, carrying roughly five times the armament of any other single ship. It was also equipped with a powerful thalaron radiation weapon, capable of stripping the life off a planet in a matter of seconds. This weapon took seven minutes to prepare. The Scimitar also held several Template:ShipClass attack fighters.
The Scimitar had primary and secondary shields. This allowed for twice the protection, giving it a backup shield. Even against the USS Enterprise-E and two Romulan Template:ShipType Warbirds, the Scimitar still had the obvious advantage.
The bridge of the Scimitar was radically different in design from any other vessel, though it did share the same basic layout as most Romulan starships.
In the center of the room was located the chair of the vessel's commanding officer. Behind his chair, both to the left and right, were consoles that required the operator to stand up. Directly in front of the captain's chair were two more stations. The command chair itself contained a built in replicator for the commanding officer's needs.
Directly behind the captain's chair was a flight of stairs that led to a higher level. Here, two more consoles were located, and access was provided to the thalaron weapon room through a pair of doors. (Star Trek Nemesis)
The shuttlebay of the Scimitar was a large area over two decks. It featured several Scorpion class attack fighters. The shuttlebay was completely destroyed when the Enterprise-E crashed with its saucer section into the Scimitar. (Star Trek Nemesis)
The name Scimitar itself is actually derived from an ancient Middle Eastern curved sword, used as far back as the mid-16th century. (citation needed • edit) The name was originally to have been used for the USS Defiant in TOS: "The Tholian Web". (The Star Trek Compendium)
In Star Trek: Countdown, the Remans were shown to have constructed smaller ships based on the design of the Scimitar. Three of these ships were used to capture the Narada, but were easily disabled by the Enterprise-E.
Scimitar-class ships appear in Star Trek Online, classified as dreadnoughts and used by the Romulans as well as the Remans.