'Hide' was a British naval undertaking by Vice Admiral Sir James Somerville’s Gibraltar-based Force 'H' to meet and escort the battleship Malaya and the MG.1 convoy from Malta to Gibraltar (20/24 December 1940).

This was part of a series of interlocking operations designed to facilitate Malaya's passage from Admiral Sir Andrew Cunningham’s Mediterranean Fleet at Alexandria to Gibraltar in 'MC2' to strengthen Force 'H' before the launch of 'Excess': two empty merchant vessels were to be passed from Malta to Gibraltar, convoys were to be passed to and from Malta, the 'MC3' sweep was to be made into the Strait of Otranto for an attack on the port of Valona in Italian-occupied Albania through which passed the bulk of reinforcements and supplies for the Italian forces attacking Greece, and carrierborne air attacks were to be made on Italian targets in the Dodecanese islands group and Italian convoy traffic between southern Italy and Libya.

The Mediterranean Fleet had sortied from Alexandria at 01.00 on 16 December with the battleships Warspite and Valiant, the fleet carrier Illustrious, the heavy cruiser York, the light cruiser Gloucester, and the destroyers Dainty, Greyhound, Hasty, Hereward, Hero, Hyperion, Ilex and Mohawk.

Early on the following day, aircraft from Illustrious bombed Axis targets on Rhodes and Astypálaia (Stampalia) before refuelling at Souda Bay on the north coast of Crete, to which York, Gloucester, Dainty and Greyhound had detached on the previous day. Rear Admiral H. D. Pridham-Wippell, second in command to Cunningham and whose 7^th Cruiser Squadron (light cruisers Ajax, Orion and Australian Sydney), screened by the destroyers Janus, Jervis and Juno, had been operating in the Aegean Sea, joined Cunningham as the weather deteriorated during 18 December.

The worsening conditions persuaded Cunningham to leave Illustrious astern as he pushed to the north in the direction of the Strait of Otranto to attack Valona, but by the time the British ships arrived off Albania the weather had turned clear and cold. Pridham-Wippell’s cruisers swept up the channel while Cunningham bombarded Valona with the 15-in (381-mm) guns of Warspite and Valiant.

On completion of this part of the 'MC2' undertaking Cunningham withdrew, steaming to the south and then to the west for Malta.

While this part of the undertaking was in progress the battleship Malaya, light anti-aircraft cruisers Calcutta and Coventry, and a mixed force of destroyers and corvettes, which also included the armed boarding vessel Chakla, covered the passage of the MW.5A and MW.5B convoys to Malta: the first comprised the 9,816-ton Lanarkshire and 12,435-ton Waiwera, both of these being British vessels loaded with stores and munitions, and the second the 1,587-ton British Volo, 3,338-ton British Empire Patrol (ex-Italian Rodi), 6,054-ton British Devis, 8,319-ton British tanker Pontfield, 9,351-ton Norwegian Hoegh Hood and 3,791-ton British Ulster Prince, the last a requisitioned Irish Sea ferry. The ships all arrived safely on 20 December, and two days later Warspite entered Grand Harbour. The battleship remained at Malta for about 40 hours.

Meanwhile Rear Admiral A. L. St G. Lyster had taken Illustrious and the fleet to the south-west in the direction of the island of Pantelleria, and on the afternoon of 21 December the carrier’s Fairey Swordfish attack aircraft had located two Italian convoys off the Tunisian coast, torpedoing two supply vessels of the second without intervention by the escorting torpedo boat Vega.

On 22 December Malaya continued to the west into the Sicilian Narrows with the destroyers Hasty, Hereward, Hero, Hyperion and Ilex, and the unladen 7,529-ton British Clan Forbes and 7,529-ton British Clan Fraser, which arrived in 'Collar' (ii) and now joined the warships from Malta as the MG.1 convoy. This was associated with 'Hide'.

Somerville had departed Gibraltar at 18.00 on 20 December, taking the ships of his Force 'H' (the battle-cruiser Renown, the fleet carrier Ark Royal, the light cruiser Sheffield and the destroyers Faulknor, Firedrake, Forester, Fortune and Foxhound) together with a another destroyer force comprising Duncan, Encounter, Isis, Jaguar and Wishart for the subsidiary 'Seek') westward movement into the Atlantic to deceive, or at least raise doubts in the minds of, Algeciras-based Axis observers who quickly reported any movement of the ships of Force 'H'. After dark the ships of Force 'H' turned back to the east, passing through the Strait of Gibraltar and entering the Mediterranean in a manoeuvre which was to become Somerville’s almost invariable practice. Nevertheless, at 09.30 on the morning of 20 December Somerville had dispatched Duncan, Encounter, Isis, Jaguar and Wishart directly to the east at economical speed.

At dawn on 21 December Force 'H' linked with the destroyer force led by Duncan. Ark Royal's aircraft flew patrols ahead of the ships and maintained a flight of fighters warming up on her flight deck. At 18.00 on 21 December Duncan, Encounter, Isis and Jaguar increased speed to 26 kt and ran ahead to carry out the subsidiary 'Seek' intended to flush out or keep down any Italian submarines and ensure that the Skerki Channel was clear by the time Malaya, her accompanying destroyer screen and the two Clan Line cargo-liners approached from the east. The Italians had already struck, for during the early hours of 22 December, in the Sicilian Narrows, Hyperion had been torpedoed by the Italian submarine Serpente; she was taken in tow by her sister-ship Ilex but they approached too close to Pantelleria, thereby exposing Ilex to severe risk, and Cunningham ordered Janus, which had been sent out from Malta with the 14^th Destroyer Flotilla, to sink Hyperion and relieve Ilex.

By 09.40 Malaya's group steaming from the east had joined Force 'H', and the combined forces headed toward Gibraltar. At 17.00 on the following day, Somerville left Sheffield and five destroyers to escort Clan Forbes and Clan Fraser at 13 kt, and himself took Force 'H', Malaya and nine destroyers toward Gibraltar at 18 kt. Somerville had arrived by 10.00 on 24 December, and the other ships arrived at 14.00.

Retiring to Alexandria, Cunningham’s Mediterranean Fleet covered the movement of the ME.5A convoy, whose British ships comprised the unladen 9,776-ton Breconshire, 7,506-ton Memnon, 10,492-ton Clan Macaulay and 7,347-ton Clan Ferguson, on its passage from Malta to Alexandria.