TikTok has become "the dark web's competitor" with a thriving marketplace for counterfeit cash, drugs and prescription medication being openly advertised on the platform, a documentary maker has warned.His warning comes as Ofcom launches a formal investigation into whether TikTok is doing enough to protect children from harmful content, amid concerns over the platform's age checks and safety systems. Sam Tullen, 23, stumbled across the illegal adverts while scrolling through his For You Page before deciding to investigate them for his new YouTube documentary series, Disclosed.Alongside counterfeit currency, Sam also found adverts for prescription medication, LSD and cannabis-infused brownies and gummies.Speaking to the Mirror, he said he initially assumed the adverts were simply scams. "I thought it was someone preying on vulnerable people who had money troubles or addiction," he said. "So when it turned out to be legit it was shocking and sickening to know it's rife on the app."‌The Liverpool filmmaker said the videos appeared so frequently that they quickly became impossible to ignore. "I had a screen recording where every two or three videos an advert for counterfeit money or drugs came up," he said. "I questioned whether they were real, so I clicked through and started digging deeper."His investigation uncovered TikTok videos directing users to Telegram channels where counterfeit banknotes, prescription medication, illegal drugs and cannabis edibles were allegedly being sold. The counterfeit notes were marketed as "A++ grade" copies, with sellers claiming they were virtually indistinguishable from genuine cash.Packages advertised included £2,000 of fake notes for £200, £5,000 for £300 and £10,000 for £500. One Telegram group alone had more than 10,000 members, while videos promoting the products had amassed thousands of views. For Sam, the scale of what he found was deeply alarming.‌"When we made the episode, TikTok did ban the accounts we found, but I posted about it on Instagram and the ads are back up under new usernames."The fact they're still being served to me is insane. They're taking action when people come forward, but these accounts can just get back on the app under discreet names."He believes the sellers deliberately disguise their content to evade moderation. "They'll show a disguised envelope with money sticking out, but the prescription drug videos were showing full boxes," he said. "It's insane to think these are allowed to serve as adverts."‌Perhaps most disturbing, Sam said, was discovering the illegal trade was genuine rather than an elaborate scam. "Knowing that if someone followed it through like I did and bought the stuff, they would actually receive it. That's what's scary - just how accessible it is."The investigation also revealed what appeared to be a sophisticated criminal network operating across Britain.Sam said videos inside the Telegram groups showed printing machinery and stacks of partially produced banknotes. When he posed as a potential buyer, sellers claimed counterfeit cash could be delivered the very same day.‌"They said they had multiple couriers across the UK," he said. "I think the evidence showed it was organised crime rather than individuals."Instead of posting packages, buyers were allegedly instructed to collect counterfeit cash from hidden locations including unlocked cars and bushes. Sam also tracked down one repeat customer after spotting an unredacted phone number inside the Telegram group.The buyer admitted purchasing more than £30,000 worth of fake notes to help pay off gambling debts. "He didn't come across like he felt what he was doing was wrong," Sam said. "It felt very victimless to him."He only used machines - gambling slot machines or self-checkouts - because he believed they were less likely to detect the counterfeit notes."‌He was equally concerned by how many young people appeared to be engaging with the content. "A lot of the accounts commenting looked like late teens or people in their early twenties," he said. "Some were anonymous, but there were a good number that appeared to be genuine people."The dark web has its competitor now, which is the For You Page," he said. "Clearly these people know there are no real consequences. They might be banned, but they can just start again. They're reaching new audiences every day."His findings come as Ofcom investigates whether TikTok has breached its duties under the Online Safety Act by failing to adequately protect children from harmful content through effective age assurance measures. The regulator could impose significant fines if it concludes the platform has fallen short of its legal obligations.‌For Sam, "moderation is key" in preventing these illegal ads from popping up for users. He added: "People shouldn't be able to pay to target others with adverts for illegal services."Following enquiries made during the documentary, TikTok removed the accounts identified by Sam. However, he says new profiles quickly appeared advertising the same illegal products under different usernames.A spokesperson for Telegram said: "While any platform can and will be used for the sale of counterfeit goods and money, Telegram's terms of service expressly forbid such content and it is routinely removed by moderators. Moderators empowered with custom AI tools proactively monitor public parts of the platform and accept reports in order to remove millions of pieces of harmful content each day, including the sale of counterfeits."The fact that abusers must depend on evasion tactics like using other platforms to lead people to their groups is testimony to the effectiveness of Telegram's moderation."‌According to TikTok, they have banned all the accounts shared and relevant hashtags, with their community guidelines making it clear they do not allow trading, marketing or providing access to regulated, prohibited, or high-risk goods or services on the platform.An Ofcom spokesperson said: "We are working at speed to develop new rules for paid-for fraudulent ads - including those that encourage or assist fraud - for the most widely used social media and search services, and our consultation on these is currently open."And platforms already have existing duties to tackle illegal content where it isn’t part of a paid-for advert."More broadly, we’ve already opened investigations into more than 100 services under the Online Safety Act - including into Telegram – and sites and apps that fall short of their duties can expect to face the consequences."