In einem Doppeldeckerbus, der an der Endstation in Oxford eingetroffen ist, wird die Leiche von Dr. Stephen Black entdeckt. Wie es aussieht, ist der Kunsthistoriker keines natürlichen Todes gestorben.

An Oxford professor, also an amateur astronomer and recently renewed churchgoer, is found dead in the school observatory under suspicious circumstances.

Six couples gather at Chaucer College for a competitive weekend 5000 pound trivia contest but several of the participants are summarily murdered.

During a Halloween, one of Dr Hobson's college roommates is found dead with a stake through her heart and a garlic bulb in her mouth.