The Return of Doctor Mabuse (German: Im Stahlnetz des Dr. Mabuse) is a 1961 black-and-white crime film/thriller made in West Berlin. It was a West German/French/Italian international co-production directed by Harald Reinl that was the second of the 1960s CCC Films Dr. Mabuse film series, being the sequel to Fritz Lang's The Thousand Eyes of Dr. Mabuse (1960). It starred Gert Fröbe, Daliah Lavi and in his first German film, Lex Barker. The film was co-written by Ladislas Fodor and, in his first screenplay, Marc Behm. They created a science fictional plot that would be followed in the other films in the series.

It was shot at the Spandau Studios and on location around Berlin. The film's sets were designed by the art directors Otto Erdmann and Hans Jürgen Kiebach.

The German title Im Stahlnetz des Dr. Mabuse was a reference to the popular German police procedural television show of the time, Stahlnetz. In 1966, the 1960s Dr. Mabuse films were released in the United States to tie in with Gert Fröbe's fame in the role of Auric Goldfinger with this film being renamed The Phantom Fiend.