Donald Marvel

In the short story The Pearl of Price, Sir Donald Marvel, MP''' is a member of Parker Pyne's party who were on a visit to Petra in Jordan. Sir Donald is described as "a tired-looking English politician".

Carol Blundell, the rich young American heiress and fellow member of the excursion later told Parker Pyne that her father wants her to marry Sir Donald. She would never consent to marrying such a "stuffed fish". She observes that, doubtless, Sir Donald probably thought she (and her wealth) would be "good for his impoverished acres", suggesting that he is a landowner or country squire of some kind.

During a conversation over dinner at the Petra site, the topic turned to that of "honesty". Sir Donald made a remark that "once a thief's always a thief." This caused some awkwardness among some at the table. The explanation for this is only made clear at towards the later part of the story.