Okay, it looks like you posted this prior to me posting my comment above. I’m not familiar with this graphical utility, but I’m assuming that it means that your disk is visible (like, if you run ls /dev/sda, you see your disk).
So what you’ve probably got is a functioning hard drive, with a functioning partition table, and on the first partition (/dev/sda1), a LUKS layer.
I haven’t used LUKS, but it’s a block-level encryption layer for Linux. It’ll have some command to expose an unencrypted layer, and you can mount that.