Independence Day 2 has added to its roster this week, welcoming back Brent Spiner as the eccentric Dr Brackish Okun - a key character in Roland Emmerich's 1996 sci-fi spectacular.

Brent SpinerBrent Spineris reprising his Dr Okun character for Independence Day 2

Spiner was already an established TV actor when he appeared in the original movie, having spent five years in Star Trek: The Next Generation. 

Dr Okun was actually based on Jeffrey A. Okun, Emmerich's VFX supervisor on Stargate. The character appeared to be dead by the end of the original movie though Spiner has said for years that he was simply in a coma.

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Few details have been revealed about the plot for Independence Day 2 though we do know that Will Smith will not be returning. However, Jeff Goldblum and Vivica Fox are confirmed to be returning, with Liam Hemsworth, Jessie Usher and Charlotte Gainsbourg also book for roles. 

Speculation suggests that Hemsworth - best known for the Hunger Games - will play President Whitmore's (Bill Pullman) son-in-law and that Jessie Usher is playing the son of Captain Steven Hiller (Smith). 

Emmerich is currently in pre-production and should be ready for a summer shoot with a release date set for June 24, 2016 in the U.S and July 1 in the UK. Carter Blanchard, best known for the short-lived 2009 TV series G vs E, was responsible for the latest re-write of the script.

The original Independence Day opened on July 3, 1996, and took a huge $817.4 million worldwide. 

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