 Moran worked closely with Davies because of the constraints imposed by filming . Davies encouraged Moran to insert linguistic jokes similar to those in the comic book series Asterix , such as Lucius Petrus <unk> ( " Lucius Stone Right Arm " ) , TK Maxximus , and Spartacus ; the use of the phrase " I 'm Spartacus ! " refers to the 1960 film . Moran based the ancillary characters of Metella ( Tracey Childs ) and Quintus from Caecilius 's family in the Cambridge Latin Course ; the character of Evelina was the only member of the family created by Moran . At the end of Book I of the Cambridge Latin Course , Caecilius and Metella perish in Pompeii on the day of the eruption , but Quintus survives . This episode creates an alternate ending to their story , where they are all rescued by the Doctor and move to Rome . The line " You must excuse my friend , she 's from Barcelona " was a reference to an apologetic catchphrase from Fawlty Towers , attributed by the production team to Sybil Fawlty ( and forming a meta @-@ pun on the Sibylline Sisterhood ) , but also harks back to previous mentions of Barcelona by the ninth and tenth Doctors . 
