Complex sentence: On the night of his introducing Basil and Lord Henry to her, the actress plays poorly; she is no longer able to act out the false love of Shakespeare's heroines whilst filled with a true love for Dorian.
Split into simpler sentences: On the night of his introducing Basil and Lord Henry to her the actress plays poorly. Unfortunately she is no longer able to act out the false love of Shakespeare's heroines whilst filled with a true love for Dorian.