adewale akinnuoye-agbaje has added an interesting new face to "lost" and even though i didn't like new people introduced too much, i think that he's been a real enrichment.
there's something really fascinating about him. he plays the different facets of mr. eko in a very convincing way and goes from cold and brutal, to almost soft and gentle in a very believable way.
he makes mr. eko one of the most interesting and definitely the most mysterious character of the show. there's a constant feeling of having a volcano in front of you and not knowing if it is going to errupt any moment.