Inside us all is a child that believes in magic lamps and in every dream coming true.
In a recent story, one insightful reviewer commented on my use of a "convenient occurance" that bordered on the highly unlikely: a guy got mysteriously dropped into an alien dimension--the land of gorgeous barbarian babes.
I did this on purpose.
The "Stranger In A Strange Land" story has a long history, hailing back to the "golden age of sci-fi". Alan Bert Akers' "Transit to Scorpio", DC comics "Adam Strange", Just about everything ever written by Edgar Rice Burroughs: "John Carter of Mars", "Beyond the Futhers Star", and "Carson of Venus" are just a few. And it happens in fantasy and other genres as well.
These type of stories come close to forming their own sub-genre. The improbable is seen in everybody speaking English wherever Captain Kirk goes in the universe, In the way the batcar burns rubber from the batcave into Gothem in time of emergency but there's never another car on the road to get in their way. It's seen in the way the Lone Ranger manages never to kill anyone, just shooting the gun out of every outlaw's hand without ever missing. The absurd continues in the way Clark Kent musses his hair and takes off his glasses and is never recognized as Superman.
Sometimes, this is a focus on synchronicity. Synchronicity says that literally EVERYTHING has to happen sometime, no matter how fortuitous or incredible. Einstein said, "Given time and eternity, all things are possible." Some Sci-fi and fantasty writers like myself seek out the unlikely to build on, doing so tongue-in-check, knowing probability is being toturously skewed. The skewing is actually parody in disguise. It is dream fulfillment being hocked to an audience that willingly suspends its disbelief because it's fun to do so.
There is something in all of us that will "Strain at a gnat, but swallow a camel." This is what I delight in playing to. The key to making a Suspension of Disbelief work for you is simple: If it's fun and exciting, the reader will forgive the unlikeliness of anything, especially if they see that it's a wink at convention, not just bad writing. People will play along with you IF YOU DELIVER! That's all the justification a writer needs.
No one on a high octane rollercoaster ride stops halfway in the journey to bitch about how unlikely the arrangement of banks, turns, and loops are. They knew all that getting onto the ride. It's after the writer gains consent that the gloves can come off! A good rule is to always let the reader know early what kind of story/genre they're getting into. That way, you don't outrage their expectations. If a story is going to be humorous--you don't start off with high, poignant drama. If a story is going to be a tear-jerker, you don't start off with a light-hearted pie fight. A reader should be aware that a Suspension of Disbelief is being asked of them. If you are writing a supernatural story, the supernatural element needs to at least be elluded to early. You don't want it showing up in chapter three or four without the groundwork being laid.
When Ian Flemming wrote James Bond, he did so by imaging all the outragious things he ever wanted to do. Then he created a character to do them, living out his every fantasy. It's why little girls watch "Sailor Moon" anime: she is the ordinary girl that winds up transforming into the beautiful princess every girl wants to be. Our resonation with our own desires--brought to life--makes Suspension of Disbelief work. You have to know what's in the reader's secret heart and offer it to them.
So how do you know what's buried in their heart? That's the easiest answer of all: look in your own.