Yes, this is it: VT11.5 for the TEE, the Trans Europ Express.
I think it has a "Dieselpunk" - like kind of elegance
Built by MAN (Maschinenfabrik Augsburg Nuernberg) and designed by architect and industrial designer Klaus Flesche. The body was made of very thin steel and aluminium, the wheel and suspension technics were derived and developed from Kruckenberg's "Schienenzeppelin" from 1930:
The VT 11.5 was Diesel driven (two driving unit fore and aft each having 1100 hp) and introduced in 1957. There were a few experiments with Lycoming gas turbines:
but they consumed way too much fuel.
https://de.wikipedia.org/wiki/DB-Baureihe_VT_11.5
The machines were built to pull the "Trans Europ Express" which was an international project in Europe beginning in 1954 with each country building its own locomotives (an international train project still lay in the future).
The trains were expected to be able to run at 140 to 160 km/h,
be Diesel driven since a lot of european railways were not yet electrified,
to have a maximum weight of 18 tons per axle,
to "run quiet" at high speeds,
have at least 120 seats and not more than three seats per row,
have a full-equipped kitchen and diner,
rooms for pass and customs control during the trip,
had to be painted in wine-red and beige for the recognition factor.
So Aktungbby was close, but Skidman takes the cake
