This book from the series Aircraft of the Aces covers the exploits of Defiant, Blenheim, and Havocs in the RAF (with only one exception of the USAAF). It follows the chronological order of the type’s services in the RAF.
First, the book covers the day fighter role of the Defiant over Dunkirk and the Battle of Britain, when it was quickly realized the airplane needed to be flying only against unescorted bombers and therefore converted to night fighter duties. Interestingly enough Defiants and Blenheims could hold their own their own against Bf-109s, but only if flown by well-trained pilots and if the whole flight would utilize proper tactics to coordinate protection for each other.