Actors that were said to be the next big thing, but weren't

Barry Pepper. Great things were predicted for him after Saving Private Ryan, he had smaller parts in some successfull movies like Enemy Of The State, The Green Mile and We Were Soldiers but I guess Battlefield Earth had a lasting negative impact on his career.

Chris Klein. Some people thought that after American Pie he could become a succesfull leading man. Hell, I remember Premiere magazine thought he had a higher chance of becoming an A-lister than Jake Gyllenhaal (LOL!). Rollerball pretty much put an end to all these hopes.