00:00Susan Cooper - Over Sea, Under StoneEpisode 4: The Trust of LogresBBC Radio 4 Extra Duration: 30 minutes Fri 18th Nov 2016, 00:00 on BBC Radio 4 ExtraThe children near the end of their quest, over sea and under stone, but it is not just the tide closing in. With Ronald Pickup.GenresChildren'sDramaSeriesSusan Cooper - Over Sea, Under Stone Source: BBC Online