Forty and Eight is a two-deck member of the Forty Thieves family, named for the French WWI boxcars stencilled "40 hommes / 8 chevaux" - forty men or eight horses. Eight tableau columns of five cards are dealt face up over a 64-card stock, and eight foundations wait for the aces. The tableau builds down by suit, strictly one card at a time, and any single card may fill an empty column. The stock deals one card at a time to the waste - and unlike classic Forty Thieves, you get ONE redeal: when the stock runs out, the waste is turned once to form a new stock.
The redeal is the game. On the first pass through the stock, think of the waste as a queue you are ordering for the second pass: cards you bury early come back early. Dig out aces and twos at almost any cost, open an empty column before the first pass ends, and prefer tableau moves that unbury same-suit sequences - with suit-only building, a blocked suit stays blocked. Do not spend an empty column on a comfort move; a space is worth roughly one rescued king.