They don't get top billing. You know the face but can't quite place the name. Though they toil in the shadows of more famous leads, to imply that character actors merely 'support' is to vastly underrate the contributions of many remarkable entertainers: Often, it is the performance of lesser-knowns that leaps from screens large and small into the hearts of an audience, leaving them with both a lasting impression and a question that begs to be answered: 'Who the heck is that?'

As a misunderstood 19th-century rent-collector called Pancks, British actor Eddie Marsan sputters and guffaws his way through the PBS production of Charles Dickens' Little Dorrit in a performance so unexpected and brilliant, one is left underwhelmed whenever he vanishes from frame. Standing 5'8, this unremarkable-looking thespian masterfully manages to steal the epic 'Masterpiece' production from dozens of fellow ensemble actors; he's so singularly magnetizing, it's not absurd to feel the miniseries should simply be retitled 'Pancks'.

Beyond impressive, this 40-something bloke from Bethnall Green, East London: So why is his not yet a household name? British audiences have been in the know for a while: Marsan displayed his considerable comic chops as a bungling bank robber on the popular 1990's BBC sitcom "Game On." Since that time, he has managed to make notable appearances in - count 'em - over 60 film and television productions in the states and abroad. He's worked with some of the best, acting under the direction of directors Martin Scorsese (Gangs of New York), Alejandro Gonzalez Inarritu (21 Grams), Terrence Malick (The New World) and Michael Mann (Miami Vice), while holding his own opposite costars like Daniel Day Lewis, Sean Penn, Edward Norton, Natalie Portman, Tom Cruise and Will Smith. Trust us, you've seen him: He's done it all from the drama of Vera Drake and mythology of Beowulf & Grendel, to the blockbuster bombast of Hancock.

Despite taking home well-deserved awards - including London Film Critics Association and National Society of Film Critics awards for his heartbreaking turn as misanthropic driving instructor Scott in Mike Leigh's 2008 indie Happy-Go-Lucky (run, don't walk to the nearest video store) - Marsan is something of an also-ran when it comes to awards. Costars like Imelda Staunton (Nominated, Best Actress Academy Award for Vera Drake) and Sally Hawkins, who took home a Golden Globe for Happy-Go-Lucky, have received accolades in portrayals that benefited from his own. We expect this to change.

What's next for Marsan? A turn as the prickly Inspector Lestrade in the highly anticipated Guy Ritchie-helmed Sherlock Holmes (opposite Robert Downey Jr. and Jude Law) due in theaters the day after Christmas.

So, who the heck is this guy?

"When I was a kid," Marsan remarked in an interview given last year, "A lot of young actors I knew would watch On the Waterfront and study Marlon Brando's performance, but I was always watching Rod Steiger, thinking that this guy is the real deal."

Eddie Marsan - Happy-Go-Lucky © Miramax Films

Eddie Marsan is also the real deal: He may not be in the foreground, but he's certainly no wallflower.

Story by Shannon Peace

Starpulse contributing writer