This is all orginal colour film taken mostly at RAF Hemswell, Lincolnshire in 1944, home of 150 and 170 Squadrons flying Lancasters.
It is based around the preperation and execution of a raid on Berlin. We see Lancs being repaired, refuelled and bombed up. We also see some of the admin behind the planning of an operation, not just at Hemswell but at Group HQ. We then meet one particular pilot, called Flight Lieutenant Harris (later we find his real name is Bob Chandler) and his crew as they attend the pre-flight briefing.
The film then goes with Harris/Chandler in his Lanc on the Berlin raid and his return, late, and de-briefing.
At the end, it is revealed that Harris/Chandler was 22 years old at the time of this raid. I am always stunned at how young these fellows were.
It's a bit polite perhaps but if you want to get a small feel of what it was like to go on a bombing raid in WW2 this film is as good as any (I doubt us land lubbers can ever fully comprehend the experience).