 Withnail is a ferocious drunk, but he was played by the teetotaler  Richard E. Grant (qv). Finally convinced that he needed to get  drunk at least once to have the proper insight into the character,  Grant "filled a tumbler with vodka and topped it off with a bit of  Pepsi", then swilled the whole thing down. He was teased the next  day by costar Paul McGann (I) (qv) and director  Bruce Robinson (I) (qv), who assured him that he would never be so  funny on film again.