Summary: Summing up "My Friend Ben" Samantha tells how Aunt Clara, trying to summon an electrician to fix a lamp, produces Ben Franklin instead. Ben is arrested for stealing a fire engine. Aunt Clara makes Ben disappear just after Darrin puts up a thousand dollars bail to guarantee Ben's appearance at the trial.
Assistant DA Chuck Hawkins feels Ben's appearance is a publicity stunt. He tells Darrin that Ben, or whoever he is, will be prosecuted to the full extent of the law. Aunt Clara finally manages to bring Ben back. Darrin tells Ben his trial for stealing the engine will be held in two days. Samantha and Aunt Clara go to work to turn public opinion in favor of Ben. The prosecution produces a series of witnesses. Most of their testimony, calculated to damage Ben's case, is skillfully refuted by Ben himself, but he feels that Darrin and Gladys Kravitz have weakened his cause.
Samantha disappears and comes back with a plaque from the fire engine reading "Benjamin Franklin Memorial Fire Engine." Applause follows her statement that a man can't be accused of stealing his own property. Wiggling her nose, Samantha immobilizes the DA. She sums up the case that the defendant should be thanked for reminding everyone of all that Ben Franklin accomplished, and of his wisdom. Ben is acquitted, and tells Darrin he in planning a night on the town with Aunt Clara. Samantha assures Darrin they'll be all right, since they're both over two hundred years old.