“It’s not who I am underneath, but what I do that defines me,” says Bruce Wayne in the iconic Hollywood blockbuster, The Dark Knight. It’s a philosophy that inspired the top-to-bottom curation of this incredible Hampstead mansion, owned by Anglo-Russian billionaire tech entrepreneur Sergey Frolovichev, the former Bumble/Badoo social network business associate of tech tycoon Andrey Andreev.

Currently on the market for £29.95 million, the astounding mega-mansion, situated in Hampstead’s glorious Greenaway Gardens, has a secret ‘Batman lair’ in the basement, inspired by Frolovichev’s favourite film, The Dark Knight.

Originally built around 1934 in a neo-Georgian style, to designs by English architect Charles Henry Bourne Quennell, every inch of the magnificent space has been custom-designed by Frolovichev, a leader in cutting-edge digital technology, in collaboration with esteemed architectural practice SHH.

Spanning a breathtaking 14,501 square feet, it boasts seven bedroom suites, an astonishing triple-height galleried entrance hall, six reception rooms, a study, and a high-tech design workshop and studio, inspired by the famous Batman movie. A media room and health spa with gym, steam room, sauna and swimming pool complete the mega-mansion checklist.

Opening onto the extraordinary external garden terrace, the impressive main reception room provides an open-plan living, dining and entertaining area, with a separate family room on one side, while on the other sits the family kitchen and breakfast room with central island and breakfast bar. The gorgeous kitchen also has an adjoining pantry and food preparation room, allowing for large-scale entertaining and events.

In the reception room, the full-height glazing can be opened to create a flowing, inside-outside entertaining area overlooking the lower terrace and rich, blossoming gardens below. An inner hall with passenger lift to all floors provides access to a boot room and side entrance for dogs and staff, as well as a secondary staircase for back-of-house services.

The Batcave-style design of the basement studio comes complete with a secret entrance, accessed via a hidden staircase from a corner of the games room, concealed by retracting floorboards. The smart and sleek design of the corridor display cabinets and studio’s unique, bespoke ceiling lighting were also inspired by the 2008 film, and have provided the owner of the property with a highly private and secure base for designing new technology components and repairing mechanical parts.

The incredible health spa has its own entrance lobby providing access to the gym, massage room with changing and shower facilities, and indoor swimming pool bordered by spacious leisure decks, complete with a separate jacuzzi, steam room and sauna.

Sat on a bucolic plot in leafy Hampstead, the property has a gated driveway and 7,921 square feet of external terrace to the rear façade, opening onto the large south-west-facing garden. Features include a central lawn bordered by a terraced summer dining area, with pergola, stepped planters, new trees and hedging, and seasonal plants including lavender, camelia, Japanese maple trees, laurel trees, ferns and flowering trees designed to create a seasonally shifting backdrop throughout the year. At the end of the garden is a shielded sunken circular fire pit with built-in seating.

The one-of-a-kind home is being offered on a shell-and-core basis, with the retained period façade, shell and core with integrated high-tech structure and infrastructure of the mansion in place. It is predicted that the internal fit-out and interior design would take approximately 12-18 months to complete at an estimated cost of around £5-7 million, with the mansion potentially worth up to £40 million once fully completed and dressed.

With significant capital having already been invested into the structure and infrastructure of the house, including the creation of the lower ground floor extension (delivered by leading basement company Trenchco), and the addition of ground source heating boreholes to install premium, future-proofed mechanical, electrical and communications infrastructure. The completed home will have an energy-efficient ground source heating and cooling system, underfloor heating, MVHR units for fresh air delivery to all rooms, audio-visual integrated cabling for home entertainment, business conferencing and security.

Craig Draper, founder and managing director of Draper London says: “This unique trophy mansion on Greenaway Gardens provides an extraordinary opportunity for an incoming purchaser to enjoy the pleasurable finishing elements of such a project where the heavy lifting has been completed at a superlative level of quality. Located on one of Hampstead’s most sought-after addresses, the mansion could appeal to a wide range of potential buyers including a tech entrepreneur like Sergey, a local London family, an international family relocating for schools or a billionaire businessperson who enjoys working from both home and the office. This sale offers a once-in-a-generation opportunity to create one of the finest new residences in Hampstead.”

The Greenaway Gardens mansion is on the market for £29.95 million, visit draperlondon.com

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