[sirbruce]

http://tvtropes.org/pmwiki/pmwiki.ph.../DeusExMachina

Literature
•Another famous example is J.R.R. Tolkien's occasional use of Giant Eagles to whisk his heroes away from danger.
◦The Lord of the Rings catches some flak for the last-minute appearance of the Eagles to rescue Sam and Frodo. It isn't exactly a Deus Ex Machina, as Gandalf's connection to the Eagles through his fellow wizard Radagast is mentioned early on in The Fellowship of the Ring, but it's tough to expect a casual reader to remember such a tiny detail.
■As the Eagles are Manwë's messengers, this is a arguably a legitimate case of a true Deus Ex Machina.
■Tolkien called them a dangerous machine that he dared not use often with credibility. He thought them a deus ex machina, though in the books he justified them better.
■It's not just at the end of Rings. These same eagles rescue dwarves from burning trees (not only burning, but surrounded by wolves!) in The Hobbit. One of them rescues Gandalf from the roof of the Tower of Orthanc in Rings as well. Tolkien seems to have been unable to resolve the issue of characters marooned on top of high things as well as unable to resist putting them there.
■What's most irritating about the Giant Eagles is that they raise serious questions about the story's foundations, as this Bob The Angry Flower comic neatly points out.