Complex sentence: After graduation, Hannah had parts in theatre productions, films, and television, including leading roles, then broke into the "big-time" with his appearance as Matthew in "Four Weddings and a Funeral" (1994).
Split into simpler sentences: After graduation, Hannah had parts in theatre productions, films, and television, which included leading roles. He broke into the "big-time" with his appearance as Matthew in "Four Weddings and a Funeral" (1994).