First episode to feature Tom Hardy
This is one of four appearances of Cillian Murphy and Tom Hardy in the same work, the others are in Inception, The Dark Knight rises and Dunkirk.
3rd instance Paul Anderson and Tom Hardy working together with prior works being The Revenant and Legend.
Tommy writes a letter to Winston Churchill in which he claims to have fought bravely at Verdun. The battle of Verdun was a strictly French versus German battle. There were no English units at that battle. Ypres would have been a much better script choice.