After nearly 40 years of wacky, lighthearted comedic roles, actor Charlton Heston finally got serious Tuesday, accepting a part in a four-hour Biblical epic to air on TNT. 'I have spent my entire career doing pratfalls and mugging for the camera,' Heston said. 'Now I intend to wipe the smirk off my face and take on a serious, dramatic role.' In the TNT drama, titled The Holy Bible, Heston will play the Biblical character Moses. Asked if he expects the transition from comedy to drama to be difficult, Heston said: 'Get your stinking paws off me, you damned, dirty apes!' 