He left Shameless after the first episode of the fourth series along with his co-star and on screen girlfriend, Maxine Peake.
hiː lˈɛft ʃˈeɪmləs ˈæftɚ ðə fˈɜːst ˈɛpɪsˌoʊd ʌvðə fˈoːɹθ sˈɪɹiz ɐlˈɔŋ wɪð hɪz kˈoʊstˈɑːɹ ænd ˌɔn skɹˈiːn ɡˈɜːlfɹɛnd, mæksˈiːn pˈiːk.