The Double Undercut is a card move where you get one or more cards from the top of the deck to the bottom or vice verse, in the form of two cuts of the deck, leaving the rest of the deck in the same order.
An "Undercut" is pulling out a packet of cards from the bottom of the deck and placing it on top while cutting or shuffling.
A precursor is provided Expert At The Card Table (1902) on page 103, which may have been Vernon's inspiration.
To do the move get a thumb break on the top card/s with right hand, next cut the bottom half to the top above the top card/break, then take the remaining cards that are under the break to the top to complete the move.
- ↑ THE ENCYCLOPEDIC DICTIONARY OF MAGIC by Bart Whaley