There's no
MNSSHP anymore, the last one was in 2010.
Disneyland Paris only did that for three years (2008, 2009 and 2010).
It wasn't popular enough so they stopped organising it.
They also used to have a Terrorific Night at the Walt Disney Studios Park.
One in 2008, 2010, 2011 and 2012.
But that was organised by the French organisation FNAC and not DLP, and they don't do it anymore.
So now there's only the Halloween Soiree/Halloween Party on the 31st.
It starts at 19:00 and finishes at 01:00, tickets cost 42 this year.
The ticket cannot be used as an entry ticket for the day.
Also guests who don't have tickets can't stay in the park at night.
For guests without tickets the park closes at 19:00.
They don't close the park entirely.
You just have to get a wristlet during the day, with your special evening ticket, and every couple of meters (throughout the entire park) security is checking to make sure everyone after 19:00 has a wristlet. They do this the entire night. If you don't have one, they immediately escort you to the exit of the park. No exceptions. So you can't just hide somewhere until they stop checking to stay for the evening without paying or something.
I've done the Soiree a few years in a row, and a couple of years back there was a lot of extra entertainment. Special characters, a special show purely for that evening, special fireworks, a parade purely for that evening, the Fantillusion Parade also came out extra and there was a party in the middle of Main Street USA with a DJ playing live. It was a lot of fun and also definitely worth the money. It was also a lot cheaper, only 25.
HOWEVER since 2012 they hardly do anything. No more special parades, shows, fireworks, party etc. All there is now is a 20 minute show called Dr Facilier's Carnival-Loween, which is held in Frontierland on the Molly Brown. And Buzz Lightyear is "DJ-ing" for about half an hour in Discoveryland. The rest of the characters that come out for meets are the same ones as during the day. That's it, there's nothing more to do.
Also don't expect to do any rides that evening. There are only a few rides/attractions open that evening and queues are absolutely massive. Literally queues of 4 hours, it's crazy.
For everyone who saw photos of last year:
Last year the Soiree was a big extravaganza. There were like 30 characters out, lots of special ones who never make appearances. For example Cheshire Cat, March Hare, the Hyena's, ShellieMay and the Three Caballeros came out for meets. However the reason for this was that a Saudi Arabian prince was visiting, who visits DLP every once in a while, and he pays A LOT of money for all these characters. He used to get his meets with all these kind of characters "private", as in..for himself and his entourage, but in the public eye of the normal visitors who had to watch from a distance. There were so many complaints about the way this worked, that last year DLP decided to give him his private meets and afterwards send the characters out for the normal visitors. The prince will not be attending the Soiree this year, so therefor also no extravaganza. That was just a one time thing. So if you saw photos and video's from last year..don't base your expectations purely on that. You will be disappointed.
I will be attending the Soiree this year, but this is only because a lot of friends of mine will be going to and we're doing a big meet up, also with some people from the Disney fan community. But if you want my honest opinion: it's not worth the ridiculous amount of money anymore. During the day it's so much more fun with Jack Skellington and Sally, Duffy in his Pumpkin outfit, Goofy with his candy machine, the Villains mix and mingle meet and the Halloween cavalcade.