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Unfaithful Partner Investigations

LOI Investigations specialises in Infidelity Investigations Services, offering discreet surveillance and evidence gathering within UK legal boundaries.

Missing Persons Tracing

Finding missing persons requires a wide range of expert skills, access to global networks and the ability to source accurate information quickly. Tracing nationally and worldwide.


At Line of Inquiry, we have our own in-house surveillance Investigators, led by a former military intelligence officer.

Worldwide Phone Tracing Services

LOI Investigations offers a GDPR-compliant UK & Worldwide Mobile Phone (Registered, Pay-as-you-go (burner phones), VOIP(Voice Over Internet Providers)) and Landline Tracing service. Obtain the full name, registered address, duration at the address, and additional connected information with utmost confidentiality.

Asset Tracing/Fraud

Our team is highly skilled at identifying cases of fraud and embezzlement, even when they are obscured by complicated corporate, nominee or trust structures and disbursed across multiple jurisdictions and countries.

Affordable & Competitive Rates to Suit any Budget

Offering a Balance of Cost-Effectiveness and Unparalleled Expertise in Investigative Services, Tailored to Meet Your Specific Needs

Private Investigators UK & Global All Services Agency

Rated as one of the best private investigations and business intelligence companies in the world.
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Family Law

Pre and post-divorce, lifestyle and financial investigations

Cyber solutions

Social media, online harassment, global database access, catfish investigations, cyber security intelligence. High success rate!

Whatever you want to know, we will get you the answer.

Full services Agency for private clients, business, lawyers, families and VIPs.

Independently audited at 97.3% success rate.

LOI Investigations specialize in the most complex UK and multi jurisdiction matters to private individuals business, corporates, VIPs and celebrities from tracing missing persons UK & Worldwide & or their assets, Litigation Support & Arbitration, Mergers & Acquisition Support, Integrity and Investigative Due Diligence, Fraud, High net worth divorce, separation and family issues. Covert Surveillance, Problem Solving and Cyber Solutions, Difficult and Unusual Cases.

All types of investigations undertaken UK & Worldwide

LOI guarantees absolute discretion and client confidentiality.

LOI Investigations, leaders in complex and major investigations. We are experts in obtaining accurate hard to obtain hidden information legally and globally in total confidence. 

UK : 0800 1 939 333
Worldwide : +44 800 1 935 777

Calls answered 24hrs a day by qualified professional investigators.


missing persons investigation

Missing Persons Tracing

Searching for a missing person in the UK or worldwide? LOI Investigations offers private investigator services to locate lost friends, family members, or debtors. Utilizing the latest investigative techniques, our experienced team provides effective and discreet missing persons investigations.

Unfaithful Partner Investigations

LOI Investigations offers specialised Infidelity Investigations Services, designed to provide you with concrete evidence and peace of mind. Our highly trained investigators employ discreet surveillance techniques. Reach out to us for a confidential and comprehensive consultation.


At Line of Inquiry, we offer in-house surveillance investigators led by experienced professionals, including a former military intelligence officer and a Senior Surveillance officer with 23 years’ experience. Our surveillance services, available across the UK and worldwide, include mobile and static solutions, under-cover work, and the use of advanced technology such as trackers, electronic bugs, and military-grade drones. Whether discreet or covert, our fool-proof method ensures professional evidence gathering to meet your needs.

Cyber Security Investigations

Line of Inquiry offers Cyber Security Investigation services to thwart planned cyberattacks and minimize damage. Utilizing advanced monitoring, intelligence procedures, and in-depth data analysis, we stay ahead of potential cyber threats. Our capabilities extend to accessing information from the dark web, aiding in criminal investigations, fraud, and identity theft cases. Our innovative tools and methods, combined with AI-backed automation and expert human expertise, enable us to identify different types of threats and build defense systems tailored to individual business needs.

Worldwide Phone Tracing Services

LOI Investigations offers a GDPR-compliant UK & Worldwide Mobile Phone (Registered, Pay-as-you-go (burner phones), VOIP(Voice Over Internet Providers)) and Landline Tracing service. Obtain the full name, registered address, duration at the address, and additional connected information with utmost confidentiality.

Social Media and online harassment

Line of Inquiry provides specialized services to combat Social Media & Online Harassment in the U.K., including racial abuse, threats, and cyberbullying. Working with legal experts, they use advanced technology to trace online interactions and prosecute harassers.

Asset tracing and recovery

Our asset tracing services are designed to help our clients identify hidden assets, such as bank accounts, real estate and other investments, that have been intentionally hidden to avoid detection. We use a variety of tools and technologies, including open source intelligence (OSINT), public records searches, and deep web analysis to trace and identify hidden assets. Our team of experienced investigators works closely with our clients to understand their unique needs and develop a customized asset tracing strategy that meets their specific requirements.

Background Checks

LOI Investigations specializes in accurate and thorough background checks for individuals and companies. Offering pre-employment background checks, including verification of education, employment history, and criminal record checks, our experienced private investigators ensure the safety and security of your business and personal life. Trust LOI Investigations for reliable background checks with confidentiality and fast turnaround times.
missing persons investigation

Relationship Matters, Family Issues and Divorce

Dealing with family issues and divorce? Line of Inquiry offers specialized private investigator services to assist in personal and financial matters, including hidden assets, pre-divorce background checks, and post-separation surveillance. Whether you suspect infidelity, need to assess financial status, or are concerned about child well-being, our experienced investigators handle these delicate situations with discretion and sensitivity. Contact Line of Inquiry to navigate family disputes and divorce with confidence and peace of mind.


Private Clients

We at Line of Inquiry offer a range of services for private clients, including missing persons tracing, background checks, surveillance, and asset tracing. Specialized services are also available for relationship matters, identity theft, and blackmail. Our experienced team utilizes advanced investigative techniques to provide effective and discreet solutions tailored to individual needs.


Line of Inquiry offers a comprehensive suite of services tailored for businesses. These include business intelligence, asset tracing, debtor tracing, and competitive intelligence. Specialized services extend to acquisition and mergers, investment intelligence, and supply chain risk mitigation. Our experienced team employs advanced technological tools and investigative techniques to ensure your business stays ahead in a competitive market.

Relationship Matters & Family Issues

Comprehensive support in family law matters, including relationship disputes and divorce cases. Our services extend to missing persons tracing, surveillance, and personal protection against blackmail. Utilizing advanced technology and an experienced team, we offer discreet and effective solutions tailored to the unique challenges faced by families.

Cyber Investigations

We offer a comprehensive range of Cyber Investigation services, including tackling catfishing, social media harassment, and cyber threats. Our expertise extends to cryptocurrency investigations and technical counter-surveillance. Utilizing a team of former FBI agents, we provide robust solutions to protect both individuals and businesses from various cyber risks.


We at Line of Inquiry specialize in litigation investigation and support services, offering worldwide assistance for both civil and criminal cases. Our services include fraud investigations, asset tracing, and family law support. Utilizing advanced technology and techniques, we work closely with legal teams to provide expert analysis and testimony, adhering to the highest ethical standards.

Offices In London and Globally

24/7 availability, in office, over the phone as well as online.

We can visit clients or if preferred schedule Zoom/Google Teams meetings.
Meetings in office by prior appointment.


Featured in Media

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Navigating Child Custody Disputes with Expert Private Investigators

Gain insights into how professional investigators play a pivotal role in child custody cases, offering discreet and expert services to navigate the complex terrain of family law. Discover how their investigative expertise can be a decisive factor in safeguarding children’s best interests.

Safeguarding Your Heart and Wallet: How Private Detectives Can Help in Cases of Romance Fraud

Discover the vital role of private detectives in combating romance fraud. This post delves into how expert investigators at LOI Research help uncover deceit and safeguard individuals from emotional and financial exploitation in romantic relationships.

Enhancing Corporate Security: The Vital Role of Background Checks in Hiring

Discover how comprehensive background checks are essential in the corporate hiring process, serving as a critical tool in risk mitigation and ensuring the integrity and safety of the workplace.

When to Hire LOI Investigations for Phone Hacking Concerns

Concerned about phone hacking or bugging? LOI Investigations, a leading private investigator agency in London, outlines the signs to watch for and why professional help is essential.

When to Seek Professional Help: Infidelity Investigations

LOI Investigations offers professional and discreet private investigation services for those suspecting infidelity. Learn when to seek help and what signs to look out for.

How a Private Investigator Agency Can Help Recover Scammed Bitcoin and Cryptocurrency Assets: A Quick Guide

Learn how a private investigator agency like LOI Investigations can assist you in recovering stolen Bitcoin and other cryptocurrencies. Expertise in digital forensics, global networks, and legal assistance.

The Importance of Due Diligence in Asset Tracing: A Comprehensive Guide

Discover the indispensable role of due diligence in asset tracing. This comprehensive guide delves into how due diligence complements advanced investigative techniques, offering a holistic approach to uncovering hidden assets.

Newsweek consults LOI about the disappearance and release of Monica De Leon Barba

Californian Monica De Leon Barba was kidnapped in Mexico and later freed. Expert insights from LOI Investigations were featured in Newsweek. The case delves into the psychological toll of long-term kidnappings, challenges in foreign victim retrieval, and motives. Gavin Burrows adds personal experience.

Prince Harry’s Lawyers Allegedly Utilized Hacker Who Paid Private Investigators

Welcome to the LOI Investigations Blog! In today’s article, we delve into a recent news piece published on The Times website, which discusses the involvement of Prince Harry’s legal team with a convicted phone hacker and the use of private investigators. Please note that the original article requires a subscription to The Times. Let’s explore the details and implications of this intriguing story.

The Mysterious Disappearance of Levi Davis: Unveiling the Investigation

In the perplexing case of Levi Davis, a talented musician who mysteriously disappeared, questions linger about his sudden absence and the enigmatic events surrounding it. Despite months passing since his disappearance, unexpected Instagram activity and puzzling sightings have added intrigue to the investigation. As private investigators, we delved into the shadows, uncovering perplexing details that defy explanation.

Building the Future

Have Achieved :

  • Home office full criminal record cleared all employees
  • Full Members of the Institute of Professional Investigators
  • Fully Insured and Certified.
  • Information Commissioner’s office (ICO)

Who We Are :

Line of Inquiry (LOI) has an impressive network of Cyber Investigators (Government Level trained),  specialist unit surveillance experts and many other skilled experts. We have excellent, well-placed contacts throughout the world.
Line of Inquiry Head Office is 5 Chancery Lane, London WC2A 1LG, conveniently located in the heart of the Legal District and has further offices in Switzerland, Germany, Netherlands, Malta, Monaco, Norway, Finland, Luxembourg, Cyprus, Denmark, Singapore, Japan, Thailand, Bangkok, Taiwan, Kuala Lumpur, Vietnam, Dubai, Hong Kong, Uzbekistan, Kazakhstan, Kyrgyzstan, Washington, New York, The Hamptons, Los Angeles, San Francisco, Dallas, Denver, Houston, Florida, Toronto, Melbourne, Canberra, Sydney.

Our business is to get you the information you require discreetly undetectably and in strict confidentiality.

More About Us

We are a group of highly experienced private investigators blending traditional trade-craft with modern investigation techniques. LOI is firmly established as one of the world’s leading Private Investigation consultancies, and all-round problem fixers.

The British Royal Family:

There have been many world-class successes, including when our founder worked for the British Royal family and senior Police infiltrating a group who posing as staff at a polo match Planned to steal DNA from HRH Prince Harry. Prince Charles and Prince William were also attending. Liaising directly with senior police and Prince Charles private secretary, our founder thwarted the plot successfully.
The founder of our company, was also commissioned to write a report, translated into every FIFA (Fédération Internationale de Football Association) member’s language on Press Intrusion, privacy and protection.
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Achieved Credentials


Line of Inquiry has contracted representatives who are licenced, if required in country whom are experienced, qualified, male and female investigators with the exception of Russia. We do operate and have contacts in these regions but do not have a Line of Inquiry contracted representative permanently in the country. A Line of Inquiry contracted representative can visit you at any meeting place of your choice to discuss your case in total confidence.

We Prosecute Fake Reviews & Any Third Parties Who Copy Clone Or In Anyway Copy (Any Content On This Website Or Act In Bogus Websites And Or Any Other Type Of Outlet As Gavin Burrows. Line Of Inquiry LOI)
We know how to legally trace emails, YouTube, Facebook, LinkedIn, and Instagram posts & comments, trace email and chat box enquiries.
Even if the spurious individuals are using VPNs. We can & we will assist in the prosecution of any fake reviews and we can assist you in doing the same whether you are a private individual, sole trader, SME or Corporate. We work closely with a leading London Lawyer and KC who specialise in this area and of course our own in-house Line of Inquiry Cyber Team.

Please call :
UK : 0800 1 939 333
Outside UK : +44 800 1 935 777

Chancery Lane In London
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