Plot: A card having been chosen and returned to the pack without the magician knowing what was selected. The magician removes three cards stating they will help him find the selected card, but the spectators notice that one of them IS the selected card thinking that the magician has already failed. However, after turning the 3 cards face down, the magician triumphantly produces the chosen card from the pack, the card which was down on the table changed to an indifferent one.
It's been said that Charlie Miller named it Dunbury after the Dumbarton Bridge that crosses San Francisco Bay.
- The Partagas 'Sell' - Victor Farelli in Farelli's Card Magic Part Two (1933)
- The Dunbury Delusion - Charlie Miller in Expert Card Technique (1940)
- Fours of a Kind - Jean Hugard in Royal Road To Card Magic (1948)
- Design for Laughter - Jean Hugard and Frederick Braue in Royal Road To Card Magic (1948) p. 54)
- The Dunbury Delusion - Bill Simon in Effective Card Magic (1952)
- Dunbury Delight - Frank Garcia & Dai Vernon in Million Dollar Card Secrets (1972)
- Dave's Delight - Dave Lederman in Super Subtle Card Miracles (1973)
- Deep Dunbury - Ed Marlo in Marlo's Magazine, Vol. 1 (1976)
- Quick Deep Dunbury - David Solomon in Marlo's Magazine, Vol. 1 (1976)
- And Counting - Karl Fulves in Packet Switches (Part Five) (1977)
- Finger on the Card - Gary Ouellet in Masters of Magic Series (1978)
- Did-Dan-Dunbury - Martin Nash in Sleight Unseen (1979)
- Bauer's Delusion by Ron Bauer in Genii 1982 March, Vol. 46, No. 3.
- Make Mine Dunbury Well - Jon Racherbaumer in CardMagic (1983)
- The Coué Test - Roberto Giobbi in Card College, Vol. 1 (1996)
- Dunbury Delusion Revisited - David Solomon in Solomon's Mind: The Card Mysteries of David Solomon (1997)
- The Dunbury Delusion in Genii 2000 September, Vol. 63, No. 9, page 61. Jim Swain had a great handling of it using something he called the Cool-Out Move.
- Bob’s Delusion by Bob King in Precursor (Number 83, July 2002)
- Dunbury Drop - David Ben in Tricks (2003)
- Easy to Master Card Miracles, Vol. 4 by Michael Ammar.