Zack Allan

Zack Allan works security aboard Babylon 5, a big, affable presence who's more comfortable following orders than giving them. He's not naturally suspicious or political, which makes him uneasy when the station's power struggles start pulling him into decisions above his pay grade. He wants to do his job, keep his head down, and trust the people above him.

Conaway plays him as an ordinary man in an extraordinary place, someone whose decency is tested precisely because he isn't a hero by temperament. The show uses him as a barometer for how far things have gone wrong: when Zack gets nervous, the audience should too. It's a quietly effective piece of casting against type.