Simplify the following text for a Grade 5 native English-speaking person.
Original: One of them was for the fledgling WB Network show Dawson 's Creek . Van Der Beek won the title role of `` Dawson Leery , '' and the show 's 1998 debut was a success that helped to establish the network and its cast , which included Katie Holmes , Michelle Williams , and Joshua Jackson .
Simplified: He is best known for his role as Dawson Leery in Dawson 's Creek alongside Katie Holmes .