14 March -- Among the highlights of this year 's Comic Relief telethon is Prime Cracker starring Helen Mirren and Robbie Coltrane as their respective characters .
Prime Cracker is a short spoof crossover of ITV stablemate crime dramas Prime Suspect and Cracker .
14 March -- Among the highlights of this year 's Comic Relief telethon is Prime Cracker , a short spoof crossover of ITV stablemate crime dramas Prime Suspect and Cracker , starring Helen Mirren and Robbie Coltrane as their respective characters .