Is there any significant risk in a mutual fund Roth IRA?

I am looking into setting up a T Rowe Price Roth IRA with strictly mutual funds. Obviously, there is inherent risk in any kind of stock investment, mutual or otherwise, but is there any chance I could LOSE money in this type of account? I don’t want my retirement savings to be in a volatile investment account…I know mutual funds are less risky than individual stocks but what if the mutual funds perform terribly?