Complex sentence: Contrary to some accounts Allen was not present at the execution of Ruth Ellis, the last woman to be hanged in the UK, in 1955: the assistant to Albert Pierrepoint on that occasion was Royston Rickard.
Split into simpler sentences: Contrary to some accounts Allen was not present at the execution of Ruth Ellis, the last woman to be hanged in the UK, in 1955. The assistant to Albert Pierrepoint on that occasion was Royston Rickard.