Once Upon a Time and OUaT in Wonderland

"Once upon a time.
There was an enchanted forest filled with all the classic characters we know.
Or think we know.
One day they found themselves trapped in a place where all their happy endings were stolen.
Our world."

Once Upon a Time is a fairy tale based TV series. The series involves a plethora of characters taken from various fairy tales and other popular fictional tales (usually the Disney versions of most of them), but the main action is centered on Snow White and her family. With quite an interesting twist!

The series starts with Snow and Prince Charming's wedding (after he wakes her up from the sleeping curse with a kiss), which Regina the Evil Queen (not dead in this one!) crashes to tell them to enjoy their happy day, because soon she will take away everything they love and their suffering will be her happy ending. The Evil Queen casts a powerful curse which transports all the inhabitants of the "Enchanted Forest" (the name of this realm where fairy tales are real) to "a land without magic", a.k.a. "the real world" for us, the small coastal town of Storybrook, Maine. But that's not all... they've all had their memories wiped and replaced with fake ones and their happy endings stolen! No one has any idea who they really are, and most of them are pretty miserable! Except for Regina who made herself Mayor of the town! Snow White is Mary Margaret, a mild mannered primary school teacher. A far cry from the kick-ass rebel who defeated the Evil Queen and regained her father's throne. Prince Charming is a John Doe in a coma. And no one else fares any better. Except for evil Rumplestiltskin, who is a powerful money lender in the town, Mr Gold.

The "real world" action starts when a young boy, Henry, shows up on the doorstep of 28 year-old bail bonds-person orphan Emma Swan claiming to be her son whom she gave up for adoption at birth. She takes him back to his adoptive mom... who just happens to be Regina in Storybrook! It's all part of his plan. He needs to convince Emma that everyone in the town is a fairy tale character and that she is really Snow White and Prince Charming's daughter whom they sent away ahead of the curse because she was destined to be the "Saviour" and the one who will break the curse (because of course every magical curse can be broken). He also says time doesn't pass there, no one has aged a day in the 28 years since the curse was cast (which explains why her parents are basically the same age as her, weird! Although they have yet to explain how Henry himself has grown in his 10 years there, or how Regina adopted him in the first place.), and that no outsiders have entered the town before her (which awakens Regina's curiosity about this Emma person). She ends up sticking around in Storybrook - much to Regina's chagrin - because she's worried about Henry and wants to help him if she can... just not by breaking any magic curse!

So the first season is all about Henry trying to get Emma to believe the story and break the curse, and the lives of the various characters in Storybrook. Simultaneously we get flashbacks to their "real selves" and their lives in the Enchanted Forest in which we learn why the Evil Queen hated Snow White so much, how she became the Evil Queen in the first place and how she was able to create and set in motion such a powerful curse, how Snow White defeated her, where Charming came from, how Rumplestiltskin fits into all of this and a zillion other quirky versions of the fairy tales and characters we all know and love. There's a lot of cross-overs between fairy tales, the same person (usually the villains) can be involved in more than one fairy tale, sometimes using the same name, sometimes known under another name.

In season two the curse has been broken and everyone has regained their memories... but they're still stuck in Storybrook with no idea of how to get "home"! Plus magic has been introduced... So worlds collide and enemies are more dangerous than before. We also discover what happened in "The Enchanted Forest" after the Curse hit (some people were left behind, and it ain't pretty!). The third season takes us to Neverland in the present time, and then back to Storybrook, with more Enchanted Forest (and Oz!) flashbacks. In season four we follow once again the traditional Storybrook main thread, with flashbacks to other lands (Enchanted Forest, Arendelle...) to fill in the background of new characters and their relationship with our main stars.

Alice, Knave, Red Queen, Genie, Jafar

In 2013 the series creators decided to launch a spin-off, Once Upon a Time in Wonderland! This one is centred on a grown-up Alice who escapes from a mental institution in Victorian-era England (locked up because she kept insisting Wonderland was real and had been there several times) and returns to Wonderland to rescue her true love Cyrus, a genie, whom she believed had been killed by the Red Queen. She is aided only by Will the Knave of Hearts, and has to face both her old antagonist the Red Queen and the evil Jafar who has his own nefarious plans for the genie. In this series the flashbacks show us some of Alice's previous adventures in Wonderland, and bits and pieces of Will's past (and his connection to the Red Queen).

Tales and characters covered so far (I think, I might be missing some): 

• Snow White -> a kick-ass Snow White, Prince Charming (yes, that's what they call him!), the Evil Queen, the Huntsman, the Seven Dwarfs
• Aladdin -> Jafar, Genie
• Alice in Wonderland -> Alice, the Mad Hatter, the Queen of Hearts (another fun twist), the Red Queen, the White Rabbit, the Caterpillar, the Cheshire cat
• Beauty and the Beast -> Belle and the Beast (another interesting twist to that one)
• Cinderella -> Cinderella and her Prince (just a cameo by them really)
• Frankenstein -> Dr Frankenstein and his monster
• Jack and the beanstalk -> Jack (sex change!), giants 
• The Little Mermaid -> Ariel, Eric, Ursula (double, again a fun twist!)
• Little Red Riding Hood -> a sexy grown-up Red, her Grannie, the wolf (cool twist there!)
• Mulan -> Mulan
• Peter Pan -> Peter Pan, Captain Hook, Tinkerbell, the Lost Boys (Hook is still a pirate, but Pan's really the evil one there!), Wendy, John and Michael Darling
• Pinocchio -> a grown-up Pinocchio, Gepetto, Jiminy Cricket, the Blue Fairy
• Rumplestiltskin -> Rumple, the Miller's daughter (again more twists)
• Sleeping Beauty -> Aurora, Philip, Maleficent (guess who she's friends with!)
• The Wizard of Oz -> the Wicked Witch of the West, flying monkeys
• Frozen -> Elsa, Anna, Christof, Hans & his brothers
• 101 Dalmatians -> Pongo, Cruella DeVil

and of course, of utmost interest to us!!!

• Arthurian legends: Lancelot, Excalibur
• Robin Hood tales: Robin Hood, Marian, Merry Men (Little John, Will Scarlet), the Sheriff of Nottingham. The Once Upon A Time wikia page has a whole post on the episodes in which Robin Hood appears and his storylines.

Episodes that include Arthurian or Sherwood characters:

(episode names link to the individual blog posts)

• Lady of the Lake (s02e03) in which Lancelot crosses paths with Snow White in the Enchanted Forest, both in flashbacks and in the present.
• Lacey (s02e19) in which Robin Hood gets involved with "Beauty and the Beast" and steals something from Rumplestiltskin (baaaaad idea!).
• Heart of the Truest Believer (s03e01) in which we are introduced to a new Robin Hood (change in actors).
• Lost Girl (s03e02) in which Excalibur makes an appearance.
• Quite a Common Fairy (s03e03) in which Robin Hood helps Neal and repays a debt to Rumplestiltskin, and we find out how he is connected to another key character. 
• Forget Me Not (Wonderland, s01e03) in which we see how Will Scarlet joined - and left - Robin Hood's band of Merry Men. (as Will is one of the main characters in Wonderland, I won't review/link to any other episodes unless they touch specifically on the topic of Will as one of Robin's men)
• In "Wicked vs Evil", the second half of season 3, Robin Hood arrives in Storybrooke! His life there, as well as his life during the previous year in the Enchanted Forest are depicted throughout the 11 episodes, including his inclinations towards a certain "evil" character...
• There's no Place like Home (s03e22), in which Maid Marian arrives in Storybrooke by a (un)fortunate accident! Involves time travel and someone forgetting the basic rules of time travel (don't mess with the past!)...  Her arrival creates quite a stir and will have long reaching consequences for both Robin and other key characters.
• Season 4 - Robin and Marian in Storybrooke... and NYC!
• Heart of Gold (s04e18) in which we discover how Robin of Lockley became Robin Hood, how he got to be so "magically" good at archery, and how he came up with his code of conduct (only steal for the benefit of others).