Hollywood buys the rights to the book before they make it, they do not own the entire Narnia catalogue, only the movie rights to three at the moment.
They will however continue the series so long as it is viable at the box office, it is my understanding that they have strategically purchased the most poular stories of the series for adaptation and will bother with the rest only if popularity in the series maintains a head of steam.
Filmmakers and audiences alike tend to get burned out if a series goes on past the magic number three, yes there are exceptions but that's exactly what they are, exceptions.
:detective:
Travis Speegle
Redeemer Presbyterian, PCA (Waco, Tx)
Pacific Cross Roads, PCA (Los Angeles, CA)
"When it comes to trustworthy theologians one can usually honor the rule of thumb that the deader the better."-Dr. John Hannah, DTS (of all places)
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