Complex sentence: An unsuccessful version of the play was running at the Alfred Theatre in Marylebone to meagre audiences, which failed to convince Bateman that another version could be a success; but Irving persuaded him and gave him a copy of "The Bells", by Leopold Lewis.
Split into simpler sentences: An unsuccessful version of the play was running at the Alfred Theatre in Marylebone to meagre audiences. Bateman remained uncertain but Irving convinced him and provided a new version of the play, "The Bells", by Leopold Lewis.