This will apparently come as a surprise, but James Bond lied to you and "being hot" does not feature particularly highly in the function, purpose and required skillset of spies, both men and women.

On a slightly more serious note, the word 'spy' covers a wide range of roles from intelligence gathering to surveillance to agent running, and the other skills of a spy are far more important than how well they can pull off slowly walking out of the sea in a bikini/swimming trunks. The vast majority of intelligence operations do not resemble the plot of a Bond or Bourne movie, and women spies play a far more important role than simply looking attractive. If you find yourself in a gunfight with an adversary then something has gone very wrong. If you introduced yourself with your real name beforehand, you're an idiot.

I'm going to focus mostly on the Second World War for this answer because it's where my expertise lies, but women have been involved in intelligence work from the start. A woman played a key role in one of the earliest recorded intelligence operations in history in the book of Joshua - two men were sent to scout out the city of Jericho ahead of the Israelite attack. They were betrayed to the King of Jericho but hid in the house of Rahab, who later smuggled them out of the city and was promised that her family would be protected during the attack.

Women have featured prominently in intelligence gathering from then until the modern day - from Aphra Behn, who became the first woman officially employed as a spy by the British government in the mid 17th Century, to Bett van Lew who ran a spy ring for the Union Army during the US Civil War.

The British Special Operations Executive in particular made good use of women as wireless operators and couriers, with women also filling in the roles typically assigned to men when their male counterparts were killed or captured. 39 women were trained by SOE in Britain and sent into France, although one local recruit and a navy officer serving on an SOE-assigned ship are generally also added to the total, with 16 dying during the course of the war.

While there was initial resistance to the idea of employing women in the field, SOE soon realised that they could successfully exploit the gendered assumptions of the German occupiers. Women, one SOE document noted, "were rarely stopped at controls [...] They were seldom picked up in mass arrests. They provided excellent cover for their movements about the country by visiting friends, carrying out shopping expeditions and later, foraging the country".

When the SOE was looking for agents, how they looked in a bikini and how fast they could run in heels was very far down the list. The main prerequisite was a perfect command of French (or the relevant local language) and an ability to think on their feet. Ability with morse code and a wireless radio were useful, ability to pull off a cocktail dress did not feature in interviews.

SOE took women from all backgrounds and stages of life. The youngest agent - Sonya Butt - was 20 years old, while the oldest - Marie-Thérèse Le Chêne - was 53 years old when she was inserted into France in 1942. Some women were unmarried, others had spouses or children. One agent even had a child with the SOE agent organiser of her local network while in the field and for a time carried out her duties while pregnant. In the typically sexist fashion of many writers of both spy fiction and non-fiction, Marcus Binney's The Women Who Lived for Danger describes the "girls" who served in SOE as "young, beautiful and brave". This is at the very least greatly misleading.

Exploiting the male gaze could act as both help and hindrance to these agents. In one instance, Maureen 'Paddy' O'Sullivan, a wireless operator for the FIREMAN network, was stopped at a German checkpoint with a wireless radio set in a suitcase strapped to her bike. She was able to distract either one or two German soldiers manning the checkpoint by agreeing to go on a date with them - an assignation that she subsequently never kept. One female SOE agent interviewed by the historian Juliette Pattinson described her exploitation of German soldiers' sexist attitudes towards woman like so:

I just sort of smiled and waved to them. All the time. Women could get by with a smile and do things that men couldn't and no matter what you had hidden in your handbag or your bicycle bag, if you had a nice smile, you know, just give them a little wink. It just happened constantly, all the time. So I got away with it. It becomes sort of second nature [...] you did that automatically.

A number of other agents record instances where chivalrous German soldiers or officers would offer to carry heavy looking bags through checkpoints or out of train stations, not knowing that they contained wireless radios, weapons or large sums of illicit cash. This could however be a double edged sword. Unwanted attention from German soldiers when an agent was carrying contraband could increase the risk of discovery. One agent was offered a cigarette by a German soldier. In an attempt to get him to leave her alone, she said she didn't smoke, but the soldier noticed the nicotine stains on her hands. She escaped without further trouble but the incident was a close call.

Indeed, while SOE's agents were able to successfully exploit the patriarchal assumptions of Germany soldiers, the male gaze is nonetheless a gaze and it would often suit the agents to go un-noticed, especially if they were hoping to avoid recognition or were actively being looked for. This was accomplished by becoming 'bland'. In one instance, Nancy Wake disguised herself as a middle-aged peasant woman to avoid recognition. In her autobiography, she describes herself as "looking like a real country bumpkin, wet hair pulled back tight, no make-up, an old-fashioned dress, and wearing a pair of the farmers old boots". The German soldiers who inspected the cart she was riding on several times "did not give me a second look, even their first glance was rather disdainful".

Similarly, Virginia Hall, when she was inserted into France for her second tour of operations with the US OSS, deliberately disguised herself as an elderly woman. Her hair was dyed grey, the wrinkles around her eyes had been drawn on with make-up and she had deliberately picked unflattering clothes. Even her teeth had been ground down to closely resemble those of an elderly peasant woman. Not only did the US send a 'bland' woman into action, they actively sought to make her so.

Sources:

Pattinson, Juliette. Behind enemy lines : Gender, passing and the Special Operations Executive in the Second World War. (2007)

Escott, Beryl, The Heroines of SOE (2010)

Vigurs, Kate. Mission France (2021)

Purnell, Sonia. A Woman of No Importance: The Untold Story of Virginia Hall, WW2's Most Dangerous Spy (2020)