I’ve run out of superlatives for the work the team RM Sotheby’s do, consistently bringing together some of the best, most desirable cars in the world for its sales.

RM’s annual sale at Monterey, California, held during Pebble Beach concours week, is no exception. The catalogue doesn’t feature quite as many mega-bucks motors as has been the case in the past, but there are still seven that could sell for more than $5 million.

But those cars aren’t necessarily the most interesting in the sale. Here’s a quick canter through the lots that grabbed my attention.

Note: at the time writing estimates have not been published

1938 Adler Trumpf Rennlimousine

Little-known German manufacturer Adler was something of an innovator, the German Citroen if you will. Its mid-size Trumpf saloon, produced from the mid-Thirties, featured cutting-edge all-round independent suspension and front-wheel-drive. But with just 56bhp from a 1,900cc, it wasn’t exactly fast.

Leading aerodynamicist Paul Jaray thought it could be. He had been experimenting with car bodies shaped like half an airship fuselage for some time. They featured a long, tapering rear, flat wing tops and radically curved windscreen to direct airflow around the car. Adler took Jaray’s ideas and applied them to the Trumpf, creating the Rennlimousine (race saloon) you see here.

This example is one of six originally built and only three that survive. It is believed to be one of the three factory team cars that raced at Le Mans in 1937, driven by Otto Lohr and Paul von Guillaume to ninth overall and second in the 2-litre class, despite being largely mechanically standard.

It subsequently raced at Spa in ’38 but crashed out. It was rebuilt by the factory, but then got lost in the fog of World War Two. It resurfaced in Germany in ’55 before being exported to the States where it passed through a number of owners. It remains in remarkably original condition. It is a true landmark of racing car design.

2013 Aston Martin DB9 Centennial Spyder by Zagato

2013 marked Aston Martin’s 100th anniversary. Some-time collaborator Zagato celebrated by building three one-off cars; a DBS Coupe, a Virage Shooting Brake and this DB9 Spyder.

The styling pays homage to the angular DBS and V8 coupes of the Seventies and Eighties. It’s extremely elegant, balanced with just the right amount of aggression. I think it’s gorgeous. The interior is pretty much standard, but that’s no bad thing.

The DB9 Spyder was built for an existing customer based in California, no doubt at astronomical cost. Since then it has covered a little over 2,000 miles. Be the perfect daily run-around in LA, where everyone has a borderline pathological need to stand out from the crowd. Though the cost of fixing even a minor parking knock doesn’t bear thinking about.

1967 Aston Martin DB6 Shooting Brake by Radford

Rumour has it Aston Martin chairman David Brown once walked into a board meeting with his dog and told the engineers to build a car the hound would fit in. So they built the boss a DB5 ‘shooting brake’ estate. He used it for many years.

Inevitably, some of Brown’s wealthy friends decided they wanted one as well. Perhaps 12 were built on the DB5 chassis and another six on the DB6. This is one of four DB6 Shooting Brakes built by Radford, with rather more elegant lines than the HLM Panelcraft alternative.

This one was ordered by a customer in New York, who specified pretty much every option Aston offered, including an automatic gearbox and aircon. It has stayed with the same family ever since. I doubt another will ever come up for sale.

1967 Bizzarrini P538

Designer Giotto Bizzarrini worked for Alfa Romeo, Ferrari and Iso before setting up on his own 1962. As the man responsible for the legendary Ferrari Testa Rossa and 250GTO, Bizzarrini was widely regarded as one of the best designers and engineers in the business, but he had a habit of falling out with his employers.

Bizzarrini concentrated on racing cars, starting with the monstrous 5300 Corsa GT racer. But wanted to build a proper prototype machine and devised the P538. It was a creative interpretation of the rules, with just enough space to squeeze and some luggage either side of the centrally-mounted driver’s seat.

A honking-great 5.3-litre Corvette V8 was mounted in the middle and Bizzarrini clothed the chassis in an achingly pretty body. Unfortunately, the FIA changed the rules and the P538 never got the chance to show what it could do in the World Championship. It proved useful in other formulae though, and as many as ten were built.

This is a later car, fresh from a full restoration to stunning condition

1957 Ford Thunderbird custom

The Ford Thunderbird was intended as a rival to European sports cars. It wasn’t that, but it was perhaps the finest slice of mid-Fifties American glamour. As such, it’s always been collectable so customised examples are rare. Of those few, this is easily one of the best.

The work of Wayne Davis, it features rebuilt suspension and brakes, a gorgeously detailed interior, one-off wheels with subtle ‘arch flares for clearance and a 500bhp, 6.2-litre Chevy V8 engine attached to a six-speed manual gearbox.

Since it was completed, the T-Bird has won several awards and been used extensively on the road.

1952 Jaguar XK120 Supersonic by Ghia

Perhaps because they were always relatively reasonably prices, Jaguars never received much attention from coachbuilders. Which makes this XK120 a real rarity. It features spectacular Supersonic bodywork, possibly the ultimate expression of Jet Age styling, designed by Giovanni Savonuzzi and built by Ghia. It was fitted to several different chassis’ including three XK120s.

This one – originally a standard coupe – was sent to Ghia by a Parisian dealer for a customer from Lyon. The engine was fettled as well, with a unique cylinder head by Conrero featuring three two-barrel Weber carburetors that helped produce a substantial 220bhp.

It was shown at several concours, but the customer never actually paid for the car, so the dealer took it back. It was finally sold on in 1969 and received a full restoration during the Nineties.

1954 Talbot-Lago T26 GSL

Despite having absolutely no money, Anthony Lago pushed through development of a new road car for 1953, the T26 GSL. He dropped the aging T26 Grand Sport chassis in favour of the more advanced Record frame, which has excellent handling thanks to independent front suspension. A three Solex carburetors were added to the 4.5-litre, six-cylinder engine, now producing 210bhp.

For a short time, that made the GSL the fastest production car in the world. Unusually, the cars were clothed at the factory with a slinky coupe body penned by Carlo Delaisse. It is a deeply lovely thing and a hugely competent grand tourer. Not that it stopped the rot at Talbot-Lago. Only around 20 were built and the company had closed by the end of the decade.

This one wears a 20-year old restoration that’s starting to wear a bit. Could easily be made perfect again, but I’d leave it as is and fell better about using properly.

View the full catalogue here

By Only Motors

All images courtesy of RMAuctions.com