Asterix the Gladiator (Goscinny & Uderzo)

In the third volume of the series, the Romans capture Cacofonix, the unbearably awful Gaulish bard, as a present for Caeser. Cacofonix is to be put in the circus to be eaten by lions, and so Asterix and Obelix come to the rescue, infiltrating the circus as gladiators. This is a very jolly volume - I love the way our two heroes completely subvert the games, and Caeser's enraged red face looking down at them.