It's powered by the Quake III Arena engine.
The game features a macabre version of Alice from Alice in Wonderland and Through the Looking-Glass.
In the game, Alice runs around with a rusty knife, using this to fight the Red Queen, the evil despot who has ruined Wonderland and has enslaved its people.
It should be noted that the game is definitely not intended for children, and has been rated 'M' (for mature).