Director Toni Harman makes her feature debut with the psycholoigcal horror film about five students squatting in an abandoned London building who find out they are not alone. Alex Wakeford wrote the script.
The project stars MyAnna Buring, Clayton Watson and Boyzone singer Stephen Gately in his film debut. Colin Salmon also makes an appearance.
Moviehouse will give the film its its market debut at Cannes.
Alto is a new genre-focused independent production company formed by Harman and Wakeford. Their other features in development include supernatural horror film Cat's Cradle.
Harman recently was selected to participate in the UK Film Council and Warp X's Darklight scheme, which backs female horror directors.
Gary Phillips, co-managing director of Moviehouse said: really delighted to be handling sales for Credo, a classically scary horror film from a new British talent.'