Complex sentence: She was originally selected to play the role of Phoebe Halliwell in the television series "Charmed"; however, she left the series after filming the pilot and Alyssa Milano took over the role of Phoebe.
Split into simpler sentences: She was originally selected to play the role of Phoebe Halliwell in the television series "Charmed". However, Rom left the series after filming the pilot and Alyssa Milano took over the role of Phoebe.