Washington, Jan 22 : Film director Terry Gilliam has revealed that actor Benicio Del Toro was `frightening' and `frustrating'' on the set of `Fear & Loathing In Las Vegas'.

The 68-year-old moviemaker feared Del Toro was "out of control" for much of the 1998 movie.

"He gets pretty deep into his character, and sometimes I thought he was out of control. What I found out is he''s frightening," Contactmusic quoted Gilliam as telling Rolling Stone magazine.

"He required a lot of handling, and, after a while, his need to be so intense wore a lot of us out.