I did a Mad Hatter's themed Bridal Shower for my sister-in-law. It wasn't the darker version, but some of the things I did that I got compliments on:
1. I scrounged flea markets & yard sales for mismatched tea cups and saucers for each place setting. Spent very little money, and NOTHING matched. Very mad hattery. Everyone took their cups & saucers as their favor.
2. I had petit fours made by our local bakery. Slightly pricey, but really worth the effect, as well as finger sandwiches.
3. Hand made invitations using my color scheme (which was bright since it was summer - lime green, hot pink & purple). Used "You mustn't be late! You mustn't be late, for a very important date!" on the front and put details inside.

Just some suggestions you could tweak to your own use. Have fun with it!!

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