All Creatures Great and Small series four airs on Channel 5 tonight as James Herriot and Helen Alderson return to Skeldale House.The couple are settling into life as a newly wed couple while waiting to hear if James will be called up to serve in the RAF. Meanwhile, Siegfried Farnon is getting to grips with his brother Tristan fighting in the war and trying to run the vet surgery without him. Elsewhere a new trainee veterinary student Richard Carmody arrives, causing complications in the house.