As promised last week, thatgamecompany's upcoming online co-operative adventure--Journey--is getting an invite only beta that begins tomorrow (June 28), and runs through July 12.

On that note, Shacknews has five codes for the Journey beta to give away.

Entering the giveaway is simple, you just have to follow a few rules:

• Leave a comment below.

• You must be 18 years or older and a resident of the United States or Canada (excluding Puerto Rico and Quebec).

• Limit 1 entry per person (Only your first comment will be counted).

• The entry period ends at 12:00PM PT tomorrow, 06/28/2011.

• At that time, we will randomly select five (5) winners to each receive one (1) code for the Journey beta, which can be downloaded from the PlayStation Network.

You must have a PSN account (which is free) to claim the title if you win. Winners will be notified via ShackMessage. You must have a Shack account to comment (also free).

Though there will be a few other ways to obtain a coveted Journey beta code, the official beta announcement on the PlayStation Blog indicates that some folks may find an invite waiting in their XMB inbox.

If you were one of the very earliest adopters of Flower, and you are a PS Plus subscriber as well, watch your XMB inbox for your invitation and entry into the beta. Additionally, we've been able to free up a limited number of additional spots for the beta. Please check thatgamecompany's Facebook page, here on the PlayStation Blog, or our media partners and their sites for code give-aways.

Unlike traditional multi-player games, Journey features no matchmaking, no chat functionality, and no online lobbies. Instead, players explore a mysterious world in which they may periodically encounter one other player at a time. Be sure to check out our Journey preview for more details.