Episode:3x02
The Enterprise Incident

Jack's Rating:

Kirk and Spock are captured by the Romulans while on a secret mission to steal a new Romulan cloaking device.

Features: The Romulans
Stardate: 5027.3
Air Date: 12/20/68
Director: John Meredyth Lucas

Jack's Review
One of only two appearances by the Romulans in the original series, this is a terrific episode. Plenty of intrigue and action. I own a t-shirt that says Vulcan Death Grip on it that uses the screenshot too.