A minor one, but in the book Jonathan playing a saxophone in his yard at three in the morning is just a hypothetical example that Lewis comes up with, as something Jonathan would do if he felt like it.It does, however, still center on the Magic 8-Ball.

The plan to find the clock still depends on Lewis doing magic in his own crazy, weird style, but it's a lot less convoluted (and more focused on this version's love of words) than the book's version.

Here, Jonathan is the one to find them in the secret room, but can't read them because they are written in code-the same sort used in the Captain Midnight serials, of which both Lewis and Isaac are/were fans.

In the book, Lewis found the plans and notes Isaac made about the clock and the doomsday cloud patterns hidden inside an old organ.In the movie, the break-in still happens, but nothing is found because Jonathan already took the key from Isaac's book and carried it with him it has to be taken from him later, after all of them are captured and Lewis's life is placed in danger. In the book, the clock key was hidden inside of a brass light fixture and stolen when Selenna (or, more likely, Hammerhandle) broke in and ransacked the house.(Not that Jonathan explained the significance of that to Lewis, either.) Also, his mistake in raising Selenna (or in this case Isaac) was much more understandable since the tomb was marked not with a name but the Omega Symbol, rather than the diamond and twin 'I's from the movie. In the book, Lewis simply raised the dead using a book he found in Jonathan's library, rather than with a special evil book of Isaac's that Jonathan had locked away.As a result, while Selenna does still do various manipulative things in the background (most notably appearing as Lewis's mother in his dreams to get him to find the book and key), she is reduced to Isaac's Dragon here (or at best, a CoDragon), rather than the main Big Bad as she was in the book. Here, it's Isaac himself (who in the book only appeared as the clock was striking and summoning him back, and dissipated when it was destroyed). In the book it was Selenna who was brought Back from the Dead by Lewis to impress Tarby (with a judicious bit of manipulation by planting her name in his mind to write in the magic circle).This leads to a minor instance of headscratching, since Lewis and Jonathan have the same last name - which makes sense in the books, but should not be the case here. The books eventually reveal that it was Lewis's father Charles who was brother to Jonathan here Lewis's mother was Jonathan's sister.And finally, not only was a reason for Isaac's misanthropy never given in detail in the book, but here it was the demon Azazel who gave him the plans for the clock, rather than it being something he invented and designed himself. Zimmerman actually tried to talk Isaac out of his plans, and tried to break into the house to end his spell/save his life, rather than simply being left in the dark as to his activities before his sudden demise. Additionally, it is shown that Jonathan and Mrs. He was even part of a magic act with Jonathan for years, before falling into despair and misanthropy thanks to his experiences in World War II and becoming the crazed, world-destroying warlock we know from the book. Zimmerman's families, this version of Isaac Izard was once a good man and a friend to Jonathan and Mrs. Adaptational Backstory Change: Aside from what is mentioned below about Jonathan and Mrs.No effort is made to make Blanchett look older or homelier she simply looks like Cate Blanchett with grey hair, also making this a clear case of Age Lift. Zimmerman in the book is in her 60s and is a fairly prototypical nice old lady next door type (who also happens to be a powerful witch), whereas in the film she's played by the very beautiful and already Older Than She Looks 49-year-old, Cate Blanchett. Here he's small and thin, with the same plot being accomplished by giving him a typically nerdy appearance and interests.

In the book, Lewis was a rather pudgy boy, which is an important plot point for why he gets picked on and tries to be friends with an athlete like Tarby (and why he tries to use the coin amulet in the sequel).

Kyle MacLachlan went missing in a forest, then came back evil.

Jack Black is once again teaching others the mystical arts, just like his animated character did in Kung Fu Panda 3.

The House With A Clock In Its Walls contains examples of:

House with the clock in the walls