Heath Ledger was in a television series .
His work comprised nineteen films , including 10 Things I Hate About You -LRB- 1999 -RRB- , The Patriot -LRB- 2000 -RRB- , A Knight 's Tale -LRB- 2001 -RRB- , Monster 's Ball -LRB- 2001 -RRB- , Lords of Dogtown -LRB- 2005 -RRB- , Brokeback Mountain -LRB- 2005 -RRB- , The Dark Knight -LRB- 2008 -RRB- , and The Imaginarium of Doctor Parnassus -LRB- 2009 -RRB- , the latter two being posthumous releases .