RIN depot ship lies at mooring buoy in estuary with Fairmile B MLs alongside to port and starboard. Cut to interior CUs of flotilla briefing - a Lieutenant-Commander pricks a chart while his junior captains look on - they leave the cabin, one officer with a map case carrying out the rolled up chart. HA onto the deck of the depot ship as ratings hand down crates of .303 ammunition to a motor launch alongside. Cut to flotilla at sea - views of other HDMLs shot over gunshield of after Oerlikon, and framed beneath the barrel of forward 2-pounder - LA of RIN captain on the bridge with binoculars - LA of mast silhouetted against 'mackerel' cloud cover at dusk - further views of companion craft, including a Fairmile B and boats in line ahead - CU of engine telegraph on the bridge, moved from STOP to FULL AHEAD, and MCU of helmsman - LS over estuary at dusk, a brilliant sky over a dark shoreline, with small craft and returning patrol boats on the river. Staged sequence depicting anti-aircraft defence - captain looks through binoculars, points and picks up megaphone to issue orders - three Indian crewmen abandon ropework and race to man Oerlikon - the gunner's cap falls off as he elevates the gun, but is retrieved by one of the gun crew, and the sequence continues with hat in place, the trainers pushing the mounting round by hand - LA through Oerlikon's spider sight - MS man on twin Lewis gun and facials of Oerlikon crew and Lewis gunner - CUs of captain using Aldis lamp and with megaphone - Oerlikon crew dismiss. Shots of captain's inspection. At sea again - LS of circling Mitchell (?) - Fairmile B passes on opposite course - LS to two HDMLs in line ahead off the starboard bow, the sun catching on the depth charges carried aft on each boat. Cut to view of the balloon barrage over anchorage. Sequence showing launch taking on ammunition from depot ship - ratings hand down crate of 500 .303 GII tracer followed by 1,000 Mk VII ball. Onboard the depot ship men load 20mm Oerlikon into drum magazine - the load is a mix of HE and solid shot - and .303 into circular Lewis magazines - ammunition boxes and two 2-inch mortars and illuminating rounds crowd the deck. HA from depot ship as a Fairmile B pulls away - the launch is heavily protected with splinter matting