Produced by the Remans but technically operating under the flag of the Romulan Empire, the Scimitar was first encountered by the USS Enterprise-E, which travelled to Romulus in 2378 at the invite of the new Praetor, Shinzon. The ship is a large vessel, roughly the size of the D'Deridex in terms of volume. It was classified by Captain Picard as a predator, and this is certainly an apt description. The ship carried very heavy armament and shielding, enabling it to remain in a battle for prolonged periods under heavy fire.

Like most Romulan ships the Scimitar is fitted with a cloaking device, but this is of a new type which is undetectable to the current generation of Federation sensor systems. There were no detectable tachyon emissions or residual anti-protons from the cloak, making accurate targeting impossible. Still worse was the fact that the Scimitar could fire all weapons whilst cloaked, much as the Klingon prototype Bird of Prey which Captain Kirk faced at Khittomer could.

When Shinzon attempted to invade the Federation Captain Picard took the Enterprise-E into battle with the Scimitar. The results were shocking; whereas General Chang's ship was unshielded and lost its cloak when the Enterprise-A scored a single hit, the Scimitar retained its cloak and was undamaged throughout numerous weapon impacts. The difficulty in scoring hits on the ship made an already lopsided battle a hopeless affair for the Enterprise.

Although two Norexan-class warbrids joined the Sovereign class ship in battle, the Scimitar was easily able to defeat these ships in a matter of minutes before turning its attention back to the Enterprise. Captain Picard did give a good account of his ship, fighting until all weapons were exhausted before then ramming the Scimitar rather than surrendering. The Sovereign's hull did appear to be rather stronger than the Scimitar's, yet although the impact did inflict considerable damage on the Reman ship even this did not stop it. Only a last desparate boarding action by Picard and Lieutenant Commander Data was able to stop the enemy vessel.

Perhaps most worrying of all, the Scimitar was designed to house a Thalaron radiation emitter system which could engulf ships or even whole planets. As a weapon of mass destruction the Scimitar would be horrendously effective, able to exterminate planetary populations with ease.

The Romulans seem unlikely to proceed with class production of the Scimitar as the design stands - the employment of a Thalaron system would likely provoke a quadrant-wide armaments race of horrific scale and scope. However, there is nothing preventing them from producing a modified design with only conventional weaponry. Should this prove to be the case, Starfleet has much thinking to do.