Idris Elba has joined the cast of the Marvel Studios’ production of Thor, which is being directed by Kenneth Branagh.   According to The Hollywood Reporter, Elba, who also has a role in Warner Bros.’ adaptation of DC’s The Losers, will portray Heimdall, the Guardian of Asgard, who stands guard on the BiFrost bridge to protect the city.

Elba joins a cast that includes Chris Hemsworth (Thor), Natalie Portman (Jane Foster), Tom Hiddleston (Loki), and Anthony Hopkins (Odin).  Ray Stevenson, Stuart Townsend, and Tadanobu Asano were recently announced as the Warriors Three (see “Warriors Three Cast”).  Branagh’s Thor movie is set to debut on May 20th, 2011.