Rory takes off after one of the cultists, who mutters some occult mantra. Rory whips out his sword and charges full speed, fearing the mantra may be a spell.
If it is, he's both getting rid of a looney zealot, and preventing harm to his comrades.
They could thank him later, he thinks, as he plunges the sword deep into the cultist's chest.
“…Judge not what a man has done, but judge what he could have done if he was a different bloke altogether. For art thou a leper? And a leper can changeth his spots…” --Rudy Wade, Misfits (Series 4, Episode 8)