In July 1941, it was decided to station a large force of heavy bombers (i.e., B-17s) on the Philippines. The original proposal was for four heavy bombardment groups, with 272 aircraft (plus 68 spares), with fighters (2 pursuit groups, approx 130 planes each). This was very ambitious, and given the available numbers of heavy bombers, not possible until many more B-17s had come off the production lines.
The first B-17s (9 aircraft) arrived in September, and 26 more followed in November. The planned schedule called for 33 more in December, 51 in January 1942, and 46 in February, for a total strength of 165 aircraft in March. The next 33 planes had begun their journey when the Japanese attacked, but had only completed the first leg.
This left 35 B-17s (and 39 other bombers, and 175 fighters) to face the Japanese attack. At the end of November, the B-17s were based at Clark Field on Luzon. This was exposed to enemy attack, and it was planned to move them to Del Monte in Mindanao. The airfield there became usable by heavy bombers on 2nd December, and half of the B-17s were moved (with the other half staying at Clark, so that the planes due to arrive in December could be accommodated at Del Monte).
Air operations were under the command of the Far East Air Force (FEAF). FEAF had received news of the attack on Pearl Harbor early in the morning of 8th December (local time), and began planning reconnaissance and bombing operations. At 8am, the B-17s (and other aircraft) at Clark Field took to the air to avoid being caught on the ground in case of surprise attack in the morning. With no early attack materialising, the bombers landed, and in the late morning 17 B-17s were being armed for an afternoon attack on Formosa. Shortly after noon, the Japanese attacked Clark Field, achieving surprise (news of the sightings of the incoming aircraft had been relayed to other fields, which flew fighters for protection, but not Clark). Many of the bombers and fighters on the ground were damaged (mostly by strafing); 12 of the B-17s on the ground were destroyed, and only 2 were left in a flyable state.
The B-17s that could be moved were moved to Del Monte, and took part in operations. Clark Field saw use as a staging field (i.e., bombers from Del Monte would land and refuel there) for some of these operations. 14 surviving B-17s were withdrawn to Australia 17-20 December; these were the only surviving aircraft of the FEAF.
The movie you describe would either be about the survivors of the attack on Clark being flown to Del Monte, or the withdrawal from Del Monte to Australia.
For lots of detail on the defence of the Philippines, and the fate of the FEAF, see
In particular, for the opening days of the war, including the attack on Clark Field, see https://history.army.mil/books/wwii/5-2/5-2_5.htm
The commander of the FEAF, Major General Lewis H. Brereton, was severely criticised for the damage at Clark. First, the aircraft were caught on the ground despite the incoming raid having been spotted. Second, he had been ordered to move all of the B-17s to Del Monte, and had only moved half. His career survived, and in March he became the commander of the new Tenth Air Force, based in New Delhi.
Yes on December 7th 1941 the US Army Air Forces Far East had on hand 35 B-17's. They were organized into the 19th Bombardment Group, and the 14th, 93rd, 28th and 30th Bomber Squadrons all equipped with B-17's.
Half of these were still present on the ground at Clark Field near Manila on the 8th and almost all destroyed or badly damaged in the initial Japanese attacks. But the 16 aircraft of 14th and 93rd squadrons were not there. After increasing tensions, and spotting of Japanese recon flights those aircraft had been sent to the newly completed Del Monte Airfield 500 miles to the South on the island of Mindanao. Which initialy was unknown to the Japanese.
These aircraft and the 5 or so damaged B-17's from Clark that could be put back into service were what was left. And for several days undertook recon missions, and small attacks on IJN convoys and ships, but without fighter escort and while being harassed and their field searched for.
However as losses mounted and the situation became even more hopeless the decision was made to evacuate those aircraft. On December 16th the 14 remaining B-17's began the long flight to Darwin Australia.
Several return flights would be made to Del Monte though, in March 1942 small groups of 3 and 2 aircraft would ferry General MacArthur's party and that of Philippines President Quezon to Australia. And later a mixed force of B-17's and B-25's staged out of Del Monte in April for attacks on Japanese positions and shipping.
Interesting enough, one of those 14 evacuated aircraft not only survived the war, but is still around today! The Swoose, serial # 40-3097, is currently in possession of the National Museum of the US Air Force in Dayton in line for restoration work.