Albert Pike

In the short story The Case of the Missing Will, Albert Pike is a confectioner who has a shop in the same Devonshire village in which Crabtree Manor, the house of Andrew Marsh, is located. As part of Andrew's challenge to his niece to prove her intelligence and obtain her inheritance, Andrew got Pike and his wife Jessie Pike to sign as witnesses to his last will which he had written in invisible ink. Poirot found the will and revealed the writing by heating it gently. He surmised that Andrew must have gotten the Pikes to sign on some pretext since the writing on the will was invisible.