Search on to find Smith's co-star

The search is on for an actor to play Will Smith's co-star in his next film, I, Robot, which is set to go into production in April.

The problem, according to casting sources, is that the actor, who will have the title role, will never be seen.

For although he will act opposite Smith for the six months the film will take to shoot, he will later be replaced by a computer generated robot for the finished product.

According to the casting call which has gone out, the actor must be about six feet tall and be prepared to play a muscular, thoughtful, gentle, kind and obedient robot.

I, Robot, which has been drawn from nine Isaac Asimov SAAC stories of the 1940s, is a thriller in which a detective in the year 2050 investigates a crime that might have been perpetrated by a robot.