Well, to be honest, he tried. There is only so much to do, and his character in that movie was a caricature - much like the TV show. Only the presence of the Divine itself could have saved that movie. He, in fact, was the only thing I liked about the movie.
I’m not so much saying that he was bad… but I could see him giving that sort of overacted performance in Prisoner, which would seem a little off. He can play the crazed escapee: but can he do the potential loving father-figure thing?
Actually, I think Jason Carter would make a great Lupin.
And besides, I’ve had a crush on him since he did B5. 
Eric Idle has to be that crazy knight from the paintings! I demand it!