Here is the good news. You can watch Tropic Thunder right now, in high definition, without breaking any laws or risking your computer. The film is widely available on legitimate streaming services.
Cruise (in fat suit, prosthetic hands, and bald cap) plays a vulgar, explosive studio executive. His dance to “Get Back” over the end credits became an instant meme. The role revitalized Cruise’s comedy reputation and led to talks of a Les Grossman spin-off (never made, but Grossman appeared in MTV Movie Awards sketches). index of tropic thunder free
Contrary to popular belief, direct downloading is not a "gray area." Downloading a copyrighted movie like Tropic Thunder (Paramount Pictures) from an unauthorized server is illegal in virtually every country with copyright laws (US, EU, UK, Canada, Australia, etc.). Here is the good news