Lancelot decides to steal a valuable diamond ring from Arthur. He goes to Arthur's house and tries to obtain entry by inserting a credit card into the lock on the front door. He is unable to open the door and returns to a bar, where he drowns his sorrows in whiskey. Guinevere, Lancelot's close friend, is disappointed when she discovers that he has failed to fulfill his criminal mission. She therefore travels to Arthur's house, where she manages to obtain entrance by using a set of skeleton keys. However, when she looks in the box in which Arthur usually keeps the ring, she discovers that it is empty. Arthur has taken the ring to a local jeweller for repairs. Merlin, who lives in the basement of Arthur's house, tells the police that he saw exactly what Lancelot and Guinevere had done and that he had heard them talk, on previous occasions, about stealing Arthur's ring. What charges, if any, could reasonably be laid against Lancelot and Guinevere?