As CBS' 'Elementary' prepares to build toward its first season finale, possibly introducing Sherlock Holmes' greatest nemesis Moriarty, we've seen the series assemble some serious star power. Not only will Vinnie Jones' Sebastian Moran return, and 'Game of Thrones' star Natalie Dormer portray Sherlock's only love Irene Adler, but 'The Mummy' star Arnold Vosloo has been tapped to join the finale in a mysterious new role. Might he turn out to be the dastardly professor after all?

Sherlock Holmes will have even more company than expected in 'Elementary's two-hour season finale on May 16, going up against a foreign shipping baron that may, or may not have ties to the ever-elusive Moriarty (who himself may be operating in New York!). TVGuide has revealed that former 'The Mummy' and 'G.I. Joe: Retaliation' Arnold Vosloo will play a major role in the two-hour finale, that of Greek shipping magnate Christos Theophilus, whose criminal past and suspected ties to Moriarty catch the attention of Jonny Lee Miller's Sherlock Holmes.

'Elementary' executive producer Rob Doherty also teased that another of 'Moriarty's lieutenants would unlock some "shocking revelations," in Christos' case a frightening personal motivation that ensures the Greek criminal will make certain to carry out Moriarty's plan. Of course, we wouldn't be too surprised to find out of Vosloo's character turned out to be Moriarty himself! Vosloo certainly has the menace for it...

'Elementary' will return with all-new episodes this Thursday, but what say you? Are you excited for the first season finale, or will it prove a major tease? Give us your theories on Arnold Vosloo's casting in the comments!