holbrook is known for his television roles. these include abraham lincoln, hays stone in "the bold ones: the senator" and capt. lloyd bucher in "pueblo". but he is best known as mark twain in comedy stage works and comedy shows. his first solo performance as twain was at lock haven state teachers college in pennsylvania in 1954. holbrook had to smoke for his role as twain. he would later name that play "mark twain tonight". he has portrayed twain longer than samuel langhorne clemens did.