What did Guy Williams die of?

Answer 1

Straight from wikipedia :)

Guy Williams (January 14, 1924 - May 7, 1989)[1] was an American actor and former fashion model, who played swashbuckling action heroes in the 1950s and 1960s, but never quite achieved movie-star status[2] despite his appearance (including hazel eyes, 6'3" height, and 190 lb. weight) and charisma,[1] which helped launch his early successful photographic modeling career.

Among his most prominent achievements were two memorable TV series: Zorro (in black and white-colorized years later by the Disney enterprise) and Lost in Space, as the father of the Robinson family.[1] The sci-fi TV program was highly popular, noted for the design of the sleek silver spacesuits, which Guy Williams wore in many publicity photos (see image at right).

His hobbies included: astronomy, chess, music (mostly classical), Fencing, tropical fish, and sailing:[1] he owned a 40-foot (12-m) ketch called The Oceana.[1]

In the 1970s, Guy Williams retired near Buenos Aires, Argentina, where he died of a brain aneurysm.[1]

Answer 2

Brain ANEURYSM