James Marsters

James Marsters is an actor/singer most famous for playing the Ensemble Darkhorse vampire Spike in Buffy the Vampire Slayer and Angel. His other most famous roles are Milton Fine (Brainiac) in Smallville, and Captain John Hart in Torchwood. He is on Caprica as terrorist leader Barnabas Greeley. He also portrays Piccolo in Dragonball Evolution. He also has provided the audio performances of most of Jim Butcher's Dresden books to date, Ghost Story being the exception.

James Marsters provides examples of:

Fake Brit: His most well-regarded roles are usually this, despite the fact that Marsters is American. Supposedly casting agents in Britain still mistake him for the genuine article.
Older Than They Look: Appearing to be in his late 20s or early-to-mid 30s, he definitely doesn't look like he's nearly 50.