THAT'S RIGHT. THE LOST FILMS IS BACK. And like a Heisei era Godzilla foe, it's mutated into its second, bigger, badder form. And it's got it all: Adam West battling the Big G in BATMAN MEETS GODZILLA? Check. A DAIMAJIN remake starring Steven Seagal? It almost happened. Ultraman teaming with a monkey monster in Thailand's 6 ULTRA BROTHERS VS. THE MONSTER ARMY? Yep, it exists--even if Tsuburaya Productions wishes it didn't.
This book covers:

Unproduced scripts like BRIDE OF GODZILLA? (1955), GAMERA VS. THE ICE MEN FROM OUTER SPACE (1966), ULTRAMAN: OPERATION GIANT (1966), OPERATION ROBINSON CRUSOE: KING KONG VS. EBIRAH (1966), GAMERA VS. TWO-HEADED MONSTER W (1971), THE TIME MACHINE II (1979), GODZILLA, KING OF THE MONSTERS IN 3-D (1983), IT ATE CLEVELAND (1984), COO FROM A DISTANT SEA (1989), MOTHRA VS. BAGAN (1990), GAMERA VS. PHOENIX (1993), GODZILLA VS. GHOST GODZILLA (1995), YAMATO TAKERU 2 (1997), and HEDORAH VS. MIDORA (2017).

Films that came close to shooting like THE VOLCANO MONSTERS (1957), which Toho produced new monster suits for, and NESSIE (1976-1979)--an aborted team-up between Hammer and Toho that sunk itself in the seventies.

Partially shot productions such as Daiei's GIANT HORDE BEAST NEZURA (1963), which had to be shut down when real rats overran the studio.

Banned films like ABOMINABLE SNOWMAN (1955), GREAT PROPHECIES OF NOSTRADAMUS (1974), and JUMBORG ACE AND GIANT (1974).

Fan films like the ambitious, still in production LEGENDARY GIANT BEAST WOLFMAN VS. GODZILLA (1983-present) and GAMERA 4: TRUTH (2003).

Oddities like the Italian colorized version of GODZILLA (1978) codenamed "COZZILLA" and even ATTACK OF THE GALACTIC MONSTERS (1983) and SPACE WARRIORS 2000 (1985)