In a prosecution for aggravated rape in the first degree, assault. and using a dangerous weapon in the commission of a crime of violence, since the testimony of a single witness, if credited by the jury, is sufficient to sustain a conviction, the People introduced sufficient evidence at the trial because, if the jury believed the victim's testimony, all elements of the charged offenses were met. However, the Superior Court erred when it sua sponte invoked Rule 12.1 to exclude the defendant's alibi witnesses without applying any balancing test. That error was plain: the jury may have reached a different outcome had the two defense alibi witnesses permitted to testify, and the severity and nature of the error justifies correction. Accordingly, the October 29, 2009 Judgment and Commitment is reversed and the matter is remanded to the Superior Court so that the defendant may receive a new trial consistent with this Opinion