Matthew McConaughey says he finds romantic comedies more difficult than serious roles.
The heartthrob star of Fool's Gold, The Wedding Planner and How To Lose A Guy In 10 Days, admits he enjoys giving all he's got in dramatic roles.
Matthew said: "In a funny way, there's more acting to do in the rom coms - the work is to keep them light."
In dramatic roles, he said: "You can hit as hard as you want. You can love as hard as you want. You can be in as much pain and hurt as much as it really hurts."
He added: "[In rom coms] you can't hit that hard, because we all know we're getting together in the end. We can pretty much cash that cheque going in."
The 41-year-old father-of-two relished getting serious in new legal thriller The Lincoln Lawyer, opposite Ryan Phillippe and Marisa Tomei.
He said: "It was exactly what I was looking for at the time. It's not really a conscious decision. I'm just naturally turned on by this kind of story and this kind of character now."
Matthew, who made his breakthrough as a lawyer in 1996's A Time To Kill, also wanted to study law as a University of Texas student.
He revealed: "That's probably why I feel comfortable jumping into these kinds of shoes. I love the world. Ideally, I love the scale of justice, guilt and innocence and right and wrong."
But as for pursuing a career in law, Matthew said: "I like this version. Be one for six months, then retire. Come back and do it again years later."