I see how he did it. its in the flip right around :38 seconds. When he's holding the deck in his hand and showing it to the camera. he pulls a card from under the top card, so we think its the 8 that is blue...but the 8 was never blue. it was always the five. He doesnt show the 8 right away, but puts it into the deck and when he flips the card over to show that its an eight, hes really pulling the blue five out from under it.

The last card is the red backed 5 of spades and the second from last is the blue backed five of spades. When he "reveals" the blue backed 8 of diamonds he is doing what is called a double lift (the 8 of diamonds is actually underneath the blue backed 5 of spades). He then puts the cards back on the deck before setting the blue backed 5 to the side. There is no blue backed 8 of diamonds.

He used what's called a hindu shuffle so the bottom card stays the red backed 5 of spades. He cuts a few times then shows the bottom card.

Low and behold the blue backed card "transforms" from the 8 of diamonds into a 5 of spades.