#stuart thomas

He's never given a name, the Tron wiki refers to him simply as "Sark's Lieutenant". His role seems mainly to be getting abused by Sark, verbally with such funny insults as "bit brain" and "null unit"...

...and sometimes physically as well:

And his final fate is to get surprised by Tron's disc and derezzed before he can do anything to fight back:

In a way, he feels like something of a predecessor to Jarvis in Tron Legacy, though with far less personality and screentime. I can't help but feel a little sorry for him, he seems to have lived a pretty miserable life as a Program. The Tron wiki does note one interesting aspect regarding his physical appearance: "Sark's Lieutenant was the only program in the ENCOM system with visible circuits on the skin of his neck, not just on his suit." It's not very apparent (possibly it's some kind of special effects mistake), but look at his neck in this closeup:

The wiki notes that the only other Program (not ISO) with such skin circuitry is Cyrus. Which is enough for me to start speculating headcanons. Are they related? Is Cyrus a copy of this Program, and Tron felt sorry for him when he met him again, and therefore decided to take him under his wing as the first Renegade? Is the fact that Tron derezzed him the first time they met the reason Cyrus goes crazy?

Anyway, the actor who played the Lieutenant/Peter is a guy named Stuart Thomas, credited as "Tony Stephano". Let's do a quick search to see what else he's done...